WASHINGTON – While all eyes are on who could be the future occupant of the White House, the battle over control in both chambers of Congress is also heating up, especially as more than a dozen lawmakers have announced their retirement.
The retirements, most of which were announced by Republicans, open up a series of key races ahead of the 2020 elections as Republicans try to fend off Democrats aiming to take control of the Senate and maintain, or perhaps grow, their majority in the House.
Here is the list of lawmakers who have announced they aren't running to keep their seats in 2020.
So far, 16 members of the House have announced they won't be running in 2020, including 13 Republicans and three Democrats.
Many of the retirements were announced over the last several weeks, including by four Republicans in Texas. Among those leaving Congress are two of House Republicans' 13 women, including the female lawmaker that was tasked with recruiting more conservative women and minorities to the body.
Jim Sensenbrenner: Republican representing Wisconsin's 5th District
Rep. Jim Sensenbrenner, who is the second-longest serving member of the House of Representatives, announced on Wednesday that he would not run again in 2020 for a 22nd term in Congress.
“I think the time has come to basically turn over the page in the 5th District,” he said in an interview with the Milwaukee Journal-Sentinel.
His solidly Republican district of suburban, exurban and rural communities north and west of Milwaukee County is likely to remain in Republican control.
Susan Davis: Democrat representing California's 53rd District
Rep. Susan Davis, who has represented the solidly blue southern California district for nearly 20 years, announced on Wednesday that she would not run again in 2020.
"I am immensely grateful to you for the repeated confidence you have shown in me," she said in a letter to constituents. "I have struggled to make this very difficult decision. I will not seek another term in Congress."
Bill Flores: Republican representing Texas' 17th District
Rep. Bill Flores announced September 4 that he did not intend to run for re-election in 2020.
"After much prayer over the past few days and following conversations with my wife, Gina, during that time, I have decided that my current term will be my last," Flores said in a statement, also noting that he intended to return to the private sector and remain politically active.
Flores has represented this Waco-area district since 2011, and won about 57% of the vote in 2018 in the reliably Republican district.
John Shimkus: Republican representing Illinois' 15th District
Rep. John Shimkus announced on Aug. 30 that he would not run for re-election in 2020. He announced his decision on KMOX radio in St. Louis. He said in a statement that he was looking forward to his "next chapter of life."
Shimkus, who has represented the district since 2003, won about 70 percent of the vote in 2018 in a solidly red district, which Donald Trump won in 2016.
Sean Duffy: Republican representing Wisconsin's 7th District
Rep. Sean Duffy announced Aug. 26 he would be leaving Congress in September.
Duffy, who has represented his district in northern Wisconsin since 2011, said in a Facebook post that he needs to step down in order to devote more time to a baby he and his wife are expecting in October that has a heart condition. Duffy's was once a true swing seat in Congress but was made more Republican in 2011 by GOP redistricting, and has also shifted right as rural areas continue to tilt toward Republicans.
Kenny Marchant: Republican representing Texas' 24th District
Rep. Kenny Marchant, an eight-term veteran, announced he wouldn't run for re-election on Aug. 5. Marchant, 68, was re-elected by a 3 percentage-point margin last year from his suburban district between Dallas and Fort Worth. He'd won by 17 percentage points in 2016 and by 33 percentage points in 2014.
"I am looking forward to finishing out my term and then returning to Texas to start a new chapter," Marchant said in a statement.
Will Hurd Republican representing Texas' 23rd District
Rep. Will Hurd, the lone Black Republican in the House and a strong critic of President Donald Trump, announced Aug. 1 that he will not seek re-election. In 2018, Hurd won a very slim victory — less than 1,000 votes — in his western Texas district.
"I have made the decision to not seek reelection for the 23rd Congressional District of Texas in order to pursue opportunities outside the halls of Congress to solve problems at the nexus between technology and national security," Hurd wrote on Twitter.
Mike Conaway Republican representing Texas' 11th District
Rep. Michael Conaway announced July 31 that he won’t seek a ninth term representing a sprawling West Texas congressional district.
Conaway announced his decision at a news conference in Midland. In a statement, he said that while serving in the House, he had asked his family "to make innumerable sacrifices." He said the time had come for him to put his family first.
Martha Roby Republican representing Alabama's 2nd District
Rep. Martha Roby, who has represented much of Montgomery and southeast Alabama in the House of Representatives since 2011, said July 26 that she will not run for re-election.
Roby did not specify a reason for her departure from Congress in a statement emailed and posted on Twitter, saying that she and her family "will be forever grateful to the people of AL-02 for giving us the tremendous privilege & honor of serving our state & country."
Pete Olson Republican representing Texas' 22nd District
Rep. Pete Olson said July 25 he won’t seek re-election in 2020, giving up his House seat that Democrats were already targeting for next year.
Olson said he’ll retire after his sixth term to “be a more consistent presence” with family. He narrowly won re-election in 2018 in his suburban Houston district.
Paul Mitchell Republican representing Michigan's 10th District
Rep. Paul Mitchell, a wealthy businessman who spent millions of his own money to win a seat in Congress, said July 24 that he will step down after just two terms.
Mitchell, who replaced former Rep. Candice Miller, R-Harrison Township, in 2017, after she stepped down, represents a safely Republican district, which includes parts of Macomb County and the Thumb.
Susan Brooks Republican representing Indiana's 5th District
Rep. Susan Brooks, one of only 13 Republican women in the House as well as the head of GOP recruitment for 2020, announced she would not run for re-election in an exclusive interview with USA TODAY on June 14.
“While it may not be time for the party, it’s time for me personally,” Brooks, 58, said. Democrats have been eyeing her district, which includes the wealthy northern Indianapolis suburban areas, as potentially flippable as Republican support has eroded in some suburban areas under Trump.
Dave Loebsack Democrat representing Iowa's 2nd District
Rep. Dave Loebsack announced April 12 that he will retire at the end of this term, after representing Iowa in Congress for 14 years.
The Iowa City Democrat, 66, who represents the southeast quarter of the state, was first elected to the House in 2006. He spent part of his career as the state's sole Democrat in either the U.S. House or Senate. "I have enjoyed beyond my expectations serving the people of Iowa’s Second District for the past 13 years," Loebsack said.
Jose Serrano Democrat representing New York's 15th District
Rep. Jose Serrano, a 16-term Democrat from the South Bronx, announced on March 25 that he has Parkinson’s disease and will retire at the end of his term.
The 75-year-old is a fixture in Bronx politics and is among Congress’ foremost defenders of Puerto Rico, the U.S. territory where he was born. First elected in 1990, Serrano is the most senior Latino currently serving in Congress.
Rob Woodall Republican representing Georgia's 7th District
Rep. Rob Woodall, who barely escaped defeat last year in a suburban Atlanta seat once considered safe for GOP candidates, announced Feb. 7 that he won’t seek re-election in 2020.
Woodall’s district was one of two Georgia congressional seats targeted in the 2018 midterms by Democrats. He won his fifth term by fewer than 450 votes. "I have realized over this past year of change—both in politics and in my family—that the time has come for me to pass the baton and move to the next chapter," Woodall said in a statement.
Rob Bishop Republican representing Utah's 1st District
Rep. Rob Bishop announced back in Aug. 2017 that he planned to retire and not run again in 2020. First elected in 2002 to the heavily red Utah district, Bishop plans to retire at the end of his current term, when his service in committee leadership expires under GOP rules.
He has served as chairman of the powerful House Natural Resources Committee, and is now its ranking member.
Five members of the Senate have announced they won't run for re-election in 2020, including four Republicans.
Democrats are hoping to take control of the chamber as they did with the House in 2018. In the midterms, though, Senate Republicans were not only able to fend off Democrats, they also picked up two seats.
But the 2020 election will differ from the midterms as the president will be on the ballot. Voter sentiment about Trump is likely to play a bigger role in determining who turns out at the polls and which party they support.
In 2020, Democrats need to gain four seats, only three if they take the White House. Twelve Democrats and 22 Republicans are up for re-election in 2020. Many of the GOP seats are in red states that previously voted for Trump but the retirement announcements could help in a number of key races.
Johnny Isakson Republican representing Georgia
Sen. Johnny Isakson announced Aug. 28 that he will retire at year's end, a departure that sets up a rare election in November 2020 when both of the state's Senate seats will be on the ballot and teeing up what could become a battle for Republicans to retain the state.
The 74-year-old lawmaker said he is leaving the job he loves because "mounting" health issues, including Parkinson's disease, are "taking their toll" on his work, family and staff.
Mike Enzi Republican representing Wyoming
Sen. Mike Enzi announced on May 4 that he would not run for a fifth term in 2020.
Enzi, 75, announced his pending retirement in his hometown of Gillette, where he owned a shoe store and “never intended to get into politics.” With Enzi’s retirement, Wyoming will have its first open Senate seat in more than a decade, though it’s expected to remain in Republican hands.
Tom Udall Democrat representing New Mexico
Sen. Tom Udall announced March 25 that he would not seek re-election in 2020, though the seat is favored to remain in Democratic control.
Udall said he believes he could win another term “but the worst thing anyone in public office can do is believe that the office belongs to them, rather than to the people they represent."
Pat Roberts Republican representing Kansas
Sen. Pat Roberts, the longest-serving member of Congress in Kansas history, announced on Jan. 4 that he won’t run again in 2020, setting up a scramble to replace him in a GOP-leaning state where Democrats are energized by key victories in last year’s midterm elections.
The 82-year-old, four-term senator was likely to have faced grueling primary and general election contests next year.
Lamar Alexander Republican representing Tennessee
After roughly a quarter-century in elected office, Sen. Lamar Alexander will retire in 2020.
The former Republican governor, who has served in the Senate since first being elected in 2002, announced in December 2018 that he will not seek a fourth term in the upper chamber. Alexander is chairman of the key Senate Committee on Health, Education, Labor, and Pensions, which handles everything from education policy to issues with the Affordable Care Act.
Contributing: Rebecca Morin, Ledyard King and Nicholas Wu of USA TODAY, Brian Lyman of the Montgomery Advertiser, Todd Spangler of the Detroit Free Press, Craig Gilbert and Molly Beck of the Milwaukee Journal Sentinel and the Associated Press
This article originally appeared on USA TODAY: Which members of Congress are not running again in 2020?