Kicking off a season of senatorial debates in key battleground states, Arizona Sen. Mark Kelly and his Republican challenger Blake Masters will face off Thursday in Phoenix for their only debate -- one week before early ballots go out in the state. Libertarian candidate Marc Victor will also participate.
The one-hour debate, hosted by the Citizens Clean Elections Commission at the Walter Cronkite School of Journalism and Mass Communication at Arizona State University, will air live on Arizona PBS at 9 p.m. ET/6 p.m. local time.
Gina Roberts, the voter education director at the Citizens Clean Elections Commission, the leading debate organizer for the last 20 years in Arizona, told ABC News that her team has been working on the midterm debates for more than year, "So it takes a lot to bring this to life, to bring this to voters -- it's quite a bit in terms of production."
Her group outsources debate questions from Arizona voters, which they then share with the debate moderators, Ted Simons of Arizona PBS and an alternating reporter from the Arizona Republic, who go over the voter-submitted questions together and come up with the discussion topics.
"Bringing these debates to voters from a nonpartisan entity that only has the goal to educate, not influence, is a really great resource for voters," Roberts added, "Because it gets all the candidates together on the same stage where Arizonans can hear directly from them on the issues that matter most."
Masters, a 36-year-old venture capitalist from Tucson in his first run for public office, has gone after the junior senator on southern border security and high inflation, while Kelly is expected to raise Democrats' concerns that Masters would support a federal abortion ban and spread baseless doubts about American elections since he has alleged, without evidence, that the 2020 presidential race was corrupt.
With former President Donald Trump's endorsement, Masters beat out five other Republican candidates in the August primary, but after swinging far-right to stand out in the bunch, he's faced criticism for an apparent post-primary pivot to being the "commonsense" candidate.
His campaign website was scrubbed in August to soften his views on abortion and the 2020 election and removed language about how Democrats "want to import a new electorate," which appeared to echo the right-wing "replacement theory" that white people are being strategically diminished. (Masters has denied any pivot in his message and likened the website scrub to a run-of-the-mill update.)
Kelly, a former astronaut and Navy combat pilot who often flies himself in a two-seater plane to events across the state, is running on bipartisan wins in the Senate, such as a bipartisan infrastructure package, the CHIPS and Science Act investing in domestic manufacturing and measures in the Inflation Reduction Act to fund drought and Colorado River relief measures and lower prescription drug costs for Arizona's seniors.
While Kelly won his 2020 race by earning more votes in the battleground than now-President Joe Biden, it's unclear if Arizona will maintain its purple hue given that southern border encounters are at an all-time high and inflation is the steepest in the country in the Phoenix-metro area, home to most of the state's voters.
Abortion access has also taken on new significance in the swing state after a judge lifted an injunction on a territorial-era, near-total ban on the procedure, with prison time for doctors, which the Republican attorney general revived in the wake of the Supreme Court overturning Roe v. Wade.
Kelly has said he supports codifying the right to an abortion with "some limits" late in pregnancy, while Masters supports the procedure only to save a mother's life. Masters told ABC News last month that he would support Sen. Lindsey Graham's proposal for a federal ban on most abortions after 15 weeks but also said a federal "personhood law" banning all third-trimester abortions could garner more support.
On the campaign trail, Masters has tried to keep the conversation on Democrats' spending in Washington and on Kelly voting with Biden 94% of the time, according to FiveThirtyEight, with Masters contrasting that record with Arizona's other Democratic senator, Kyrsten Sinema.
Still, Kelly has consistently polled ahead of Masters since the summer, according to FiveThirtyEight.
The Arizona Senate race has already surpassed $120 million in funding and is expected to reach more than $240 million, according to AdImpact, as the midterm elections are poised to be the second most expensive cycle in history after 2020 election.
Two years ago, Kelly flipped his Senate seat for Democrats in a special election triggered by the death of the late Sen. John McCain. Kelly defeated Sen. Martha McSally, who was appointed by Republican Gov. Doug Ducey, by more than 78,000 votes to serve out the remainder of McCain's term through January 2023.
Kelly became a strong advocate for gun restrictions in the aftermath of a failed assassination attempt on his wife, former Rep. Gabby Giffords, and he won his last election by pitching himself as an independent-minded candidate who would work across the aisle -- a strategy he's deployed in 2022 as well.
Masters, betting that Arizona is still a red state, joined former President Trump for a rally in Prescott in July after gaining his endorsement and will do so again on Sunday in Mesa.
Thursday marks Kelly's second debate but his first as a senator. While Masters participated in a GOP primary forum in June, Thursday is his first senatorial debate as a nominee.
"Senator Kelly looks forward to the upcoming debate where Arizonans will have a chance to see the stark choice in front of them this November," Kelly's campaign spokesperson Sarah Guggenheimer told ABC News. "While Masters will have to answer for his dangerous support of a national abortion ban and privatizing Social Security, Senator Kelly will speak directly to Arizonans about his work with Republicans and Democrats to lower costs, create jobs, and get our economy back on track."
Masters' campaign declined to comment to ABC News for this story.