Dem Rep Ruben Gallego beats Kari Lake in battle for Arizona Senate seat

Rep. Ruben Gallego, D-Ariz., has won the race for Arizona's open Senate seat, beating out Republican Kari Lake, a close ally of President-elect Donald Trump, according to The Associated Press Monday night.

Gallego has served in the House of Representatives since 2015, representing the 7th and 3rd congressional districts in Arizona. 

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Kari Lake and Rep. Ruben Gallego competed for the open Senate seat in Arizona. (Reuters)

Lake ran unsuccessfully for Arizona governor in 2022 and was defeated by Gov. Katie Hobbs, D-Ariz. Prior to her gubernatorial run, she was a news anchor for a local Arizona television station and worked in the media for 27 years. 

After the 2022 loss, she challenged the results, citing fraud concerns in the state. Lake still contends that there were significant irregularities in 2020 and 2022, echoing claims that Trump and many of his supporters have made. The concerns have led to the Republican National Committee devoting significant resources to election integrity efforts. 

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Primaries were held on Tuesday night to fill the seat being vacated at the end of this year by Rep. Ruben Gallego. (Getty Images)

Lake faced off against Pinal County Sheriff Mark Lamb in the Republican Senate primary, while Gallego had an advantage, running in the Democratic primary unopposed. 

The Fox News Power Rankings in September rated the Arizona Senate race as "Leans Democrat." Similarly, the Cook Political Report, a top political handicapper, also considered the race "Lean Democrat." 

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Sen. Kyrsten Sinema speaks at a committee on Oct. 19, 2021, in Washington, D.C. (Photo by Rod Lamkey-Pool/Getty Images)

The Senate seat is currently held by Sen. Kyrsten Sinema, I-Ariz., who was elected as a Democrat. She still caucuses with Democrats in the Senate but officially registered as an independent years ago after opposing her fellow Senate Democrats on the legislative filibuster. Sinema and Sen. Joe Manchin, I-W.Va., are credited with going against the Democrats to uphold the filibuster's 60-vote threshold. 

Both senators decided not to run for re-election. 

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Rep. Ruben Gallego and Kari Lake are battling in the Arizona Senate race. (Getty Images)

Before she announced that she was not going to seek another term, Sinema's potential run as a third-party candidate threatened to upend the Senate race, with strategists unsure how her supporters would break. 

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In polling leading up to the Senate election, Gallego frequently led Lake by single digits. He had even managed to lead his opponent in surveys that saw Trump defeating Vice President Kamala Harris. Experts speculated that his connection with Latino voters could have fueled split-ticket voting in the state, despite the practice becoming relatively rare. 

While Lake often played up her relationship with Trump, who had polled higher than her in the state, Gallego did not often do the same with Harris during his campaign. 

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