Here are the key down-ballot primaries happening on Super Tuesday

The first down-ballot primaries of the year on Super Tuesday are likely to be even more consequential than the day’s presidential contests, which are unlikely to change the trajectory of the Democratic and Republican races.

On the ballot Tuesday are primaries for US Senate and governor, but it’s the primaries for the US House – where Republicans are defending a razor-thin majority – that are by far the most important for the balance of power in Washington.

Central to the fight for control of the chamber is California. Democrats need a net gain of four seats to flip the House, and in California alone, the party is targeting seven GOP-held seats. President Joe Biden would have won five of them in 2020 had the current district lines been in place, making these so-called crossover districts potential low-hanging fruit for a party looking to flip seats.

Other states holding primaries for competitive House races Tuesday include North Carolina and Texas — and, to a lesser extent, Alabama, where redistricting has created a new district that’s much more favorable to Democrats.

The four states, and Arkansas, also have primaries for seats seen as safe for either party, but the nominating contests could serve as key ideological tests.

Only Texas and California have Senate primaries Tuesday. Republicans need to pick up one or two seats in the fall – depending on who wins the White House – to win the majority. The Texas race for GOP Sen. Ted Cruz’s seat has taken on increased importance for Senate Democrats in what is otherwise a tough landscape for them.

North Carolina is also hosting gubernatorial primaries Tuesday in the race to succeed term-limited Democratic Gov. Roy Cooper. The open-seat contest is expected to draw fierce attention in this presidential battleground state, which former President Donald Trump narrowly carried in 2020 and which Biden is hoping to flip.

Here are the key races and most important things to watch for on Tuesday:

House races that will be pivotal to the majority

The outcomes of several House primaries Tuesday will shape just how competitive these key races will be in the general election.

Most of them are in California, where candidates from all parties run on the same primary ballot, with the top two vote-getters, regardless of party, advancing to November.

The top-two primary system offers potential risks and opportunities for both parties, and nowhere is that clearer than in California’s 22nd Congressional District. GOP Rep. David Valadao, a perennial Democratic target in a Central Valley district that would have backed Biden by 13 points, is facing competition from both sides Tuesday – two Democrats and one other Republican are also on the ballot. Because it’s a four-way race, both national parties have spent money trying to make sure their preferred candidates don’t get locked out of the November election. It’s a familiar challenge. In 2022, Valadao nearly failed to make the top two, edging out Republican Chris Mathys (who’s running again this year) by about 2 points. Valadao, one of two House Republicans who returned to Congress after voting to impeach Trump in 2021, then went on to defeat Democrat Rudy Salas in the November general election. Salas is running again this year and is the Democratic Congressional Campaign Committee’s preferred candidate against state Sen. Melissa Hurtado. While Hurtado hasn’t raised significant money, her presence on the ballot could still splinter Democratic votes. Inside Elections with Nathan L. Gonzales rates this race Tilt Republican.

The 45th District, held by GOP Rep. Michelle Steel, offers Democratic voters a choice between multiple candidates in this Orange County seat. Garden Grove Council Member Kim Nguyen-Penaloza has the backing of BOLD PAC, the campaign arm of the Congressional Hispanic Caucus, as well as a handful of members of the California congressional delegation. Army veteran Derek Tran has his own congressional endorsements, as well as the support of VoteVets, which works to elect progressive veterans to Congress, and the political arm of the pro-business New Democrat Coalition. Biden would have won this district by 6 points. Inside Elections rates the race Lean Republican.

The 47th District is open because Democratic Rep. Katie Porter is running for Senate. Republicans hope former state Assemblyman Scott Baugh, who lost to Porter in 2022, will have a better shot at flipping this Orange County seat without challenging an incumbent. Tuesday will likely determine whom he’ll face – and how much the millions spent in negative advertising has shaped the Democratic primary. An outside group affiliated with AIPAC, called United Democracy Project, has been spending big to attack Porter’s endorsed successor, state Sen. Dave Min, over a DUI incident last year. (Min has apologized for driving under the influence.) Democratic attorney Joanna Weiss has the support of EMILY’s List, whose super PAC arm has boosted her on air. National Democrats haven’t gotten involved in this race other than to highlight what they see as Baugh’s weaknesses. Biden would have won the district by 11 points, and Inside Elections rates the race Tilt Democratic.

The general election matchups appear set in two key California swing seats. In the 13th District in the Central Valley, a rematch of 2022 looms with GOP Rep. John Duarte and Democratic challenger Adam Gray the only names on the ballot Tuesday. The DCCC has named Gray to its Red to Blue list for competitive challengers. Duarte defeated Gray by just 564 votes in 2022. Biden won the seat by 11 points and Inside Elections rates the race a Toss-up.

And in the 27th District, in the Los Angeles area, GOP Rep. Mike Garcia and Democrat George Whitesides, the former CEO of Virgin Galactic who’s also on Red to Blue, are heavily favored to make it out of Tuesday’s primary. Garcia has been an elusive Democratic target, but this would be the first time since a May 2020 special election that first sent him to Congress that Garcia will be facing a different opponent. Biden would have won the seat by 12 points, and Inside Elections rates the race a Toss-up.

Meanwhile, Democrats are targeting Republicans Young Kim in t he 40th District, a race Inside Elections rates Likely Republican, and Ken Calvert in the nearby 41st District, a contest rated Leans Republican. The presidential margins in both Southern California seats are tight – Biden would have carried Kim’s seat by just 2 points while Calvert’s district would have backed Trump by 1 point. Republicans are targeting Democrats Josh Harder in the 9th District, which Inside Elections rates Solid Democratic, and Mike Levin in the 49th District, which is rated Likely Democratic. Republicans are excited about potential Levin opponent Margarita Wilkinson because she’s the kind of diverse candidate the party has seen recent success with.

While California has the largest number of noteworthy House primaries on Tuesday, there are also contests in Texas and North Carolina for seats likely to be competitive in the fall. The general election matchups in a pair of South Texas seats – the 15th District, held by GOP Rep. Monica De La Cruz, and the 34th District, held by Democratic Rep. Vicente Gonzalez – look like they’re going to be rematches from 2022.

And in North Carolina, where redistricting has scrambled this year’s map, the 1st District, held by freshman Democrat Don Davis, is now the state’s only competitive seat. The Republican race to take on Davis illustrates the split within the party. The chair of the conservative House Freedom Caucus is backing Sandy Smith, who has twice lost earlier iterations of this rural northeastern North Carolina district. Smith’s ads tout that she believes Trump won the 2020 election and she tweeted about marching to the Capitol on January 6, 2021. Congressional Leadership Fund – the super PAC tied to House GOP leadership – has stepped in for retired Army Col. Laurie Buckhout.

House primaries that will likely determine the next member of Congress

Many of the primaries for open seats on Tuesday are in seats that are safe for one party or the other. That means the winner of those contests – or the eventual runoffs – will very likely be coming to Congress next year.

Several of the notable ones include California’s deep-red 20th District, where voters will be picking a successor to former Speaker Kevin McCarthy. Tuesday’s primary will decide the top-two candidates for November’s election, but there’s also a special election primary later this month to fill the remainder of McCarthy’s term through January 25. State Assemblyman Vince Fong, who has the backing of both McCarthy and Trump, is running in both races.

Another notable open safe GOP seat is North Carolina’s new 8th District, where pastor Mark Harris is making his fourth run for Congress after a failed Senate bid in 2014, a failed House bid in 2016 and a House campaign in 2018 that made national headlines. Harris was the apparent winner of that contest by 905 votes. But allegations of absentee ballot tampering, related to a consultant who worked for Harris’ campaign, stopped the state Board of Elections from certifying the result. Harris later called for a new election. But he didn’t run in the do-over election, which was won by Republican Dan Bishop. Bishop is now running for state attorney general.

In making his self-described comeback bid, Harris is spinning a Trump-like narrative. “In 2020, Democrats stole the election from President Trump. The year before, they did it to me,” he said in his announcement video.

State Rep. John Bradford, who had loaned his campaign more than $1 million by the end of the pre-primary reporting period on February 14, sparred with Harris over the ballot scandal in a recent debate. But Harris and Bradford are just two of six Republicans on the ballot here, and, under North Carolina law, an outright win requires at least 30% of the primary vote. Otherwise, the second-place finisher can request a runoff.

The first member-on-member House primary

Two Alabama Republicans elected in 2020 are facing off in the first member-versus-member primary of the cycle. In response to a court decision ordering the state to create a second majority-Black district “or something quite close to it,” the 2nd District – held by GOP Rep. Barry Moore – was redrawn to increase its Black population. Moore is now running in the new 1st District, but so is Republican Jerry Carl, who represents the current version of the 1st District.

The outcome of this race could help shape the tenor of the House GOP conference. Moore, a member of the House Freedom Caucus, has been campaigning with Rep. Marjorie Taylor Greene and touts his opposition to funding for Ukraine. Carl has donations that signal more establishment support – from the likes of the Chamber of Commerce and GOP donor Paul Singer. Both are pitching themselves as Trump conservatives in a new district that the former president would have won by 50 points.

House incumbents facing primaries

Several incumbents in safe seats are facing threats from within their own parties on Tuesday – and while those internecine contests might not necessarily affect partisan control, they can reveal a lot about where the base stands.

In Texas’ 23rd District, for example, GOP Rep. Tony Gonzales is facing a handful of primary challengers after he was censured by the state party last year “for lack of fidelity to Republican principles and priorities.” Candidates must surpass 50% of the primary vote to avoid a runoff, so any splintering of the GOP vote could hamper Gonzales.

Elsewhere in Texas, Democratic Rep. Sheila Jackson Lee faces a competitive challenge from former Houston City Councilwoman Amanda Edwards. The congresswoman, who lost a runoff for Houston mayor election in December and then decided to run for reelection, had raised just $252,000 by the end of the pre-primary reporting period on February 14, while Edwards had raised nearly $1.5 million. With a third Democrat in the race, the primary could head to a runoff.

California Senate primary

The jockeying for the late Sen. Dianne Feinstein’s seat began well before she died. And it’s only intensified since Gov. Gavin Newsom appointed Laphonza Butler to succeed Feinstein and Butler decided not to run for the full term. Tuesday’s primary will determine which two candidates will advance to November in an election that has seen more ad spending, excluding future reservations, than any other nonpresidential federal contest so far.

Democratic Rep. Adam Schiff, who led Trump’s first impeachment prosecution, has dominated the airwaves as he tries to cast the race as a two-way contest between himself and former Los Angeles Dodgers star Steve Garvey, who’s running as a Republican. Schiff’s ads argue that Garvey poses a threat to Democratic control of the Senate and that the congressman is the one to stop him.

Rep. Katie Porter, who came to Congress in the 2018 blue wave, is attacking that strategy in her own ads that tout her refusal of corporate PAC money and showcase her signature whiteboards. Rep. Barbara Lee, who was the only member of Congress to vote against the 2001 authorization for use of military force after 9/11, has the backing of an outside group called She Speaks for Me. Lee supporters have touted the fact that she would bring diversity to the Senate. Butler – who won’t be returning next year – is currently the only Black woman serving in the chamber.

Texas Democratic Senate primary

US Rep. Colin Allred, a former NFL player who flipped a Dallas-area House seat in 2018, appears well-positioned financially to win the Democratic nod to take on Republican Sen. Ted Cruz, who only faces token opposition in his primary. Allred ended the pre-primary reporting period on February 14 with more than $8 million the bank. He will need to clear 50% of the vote to avoid a runoff.

Allred’s main competition appears to be state Sen. Roland Gutierrez, who represents Uvalde. But Gutierrez hasn’t been able to assemble anywhere near the money or endorsements the congressman has.

North Carolina gubernatorial primaries

Both parties are picking their nominees Tuesday in one of only two states with competitive gubernatorial races in 2024 (New Hampshire is the other). On the GOP side, the front-runner is the Trump-backed Lt. Gov. Mark Robinson. He’s a controversial figure whose past hard-line stances on abortion Democrats may try to use against him – and against Republicans up and down the ticket.

On the Democratic side, state Attorney General Josh Stein is the leading contender. Their likely matchup will overlap with the focus from the presidential candidates on this battleground state.

CNN’s David Wright contributed to this report.

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