By Richard Cowan
WASHINGTON (Reuters) - Arizona Republican Kari Lake, a far-right ally of Donald Trump, on Tuesday is expected to announce her candidacy for her party's U.S. Senate nomination, in what could be a highly competitive three-way general election race in November 2024.
Arizona is already one of the most politically competitive U.S. states but its Senate race became all the more so after Senator Kyrsten Sinema in December dropped her Democratic affiliation and declared herself an independent.
Sinema has not yet said if she will seek reelection but Democratic U.S. Representative Ruben Gallego, a liberal and former Marine with Iraq war combat experience, is making a bid for the Democratic nomination for that seat.
Arizona is one of eight competitive seats Democrats will be defending in 2024 as they try to protect their narrow 51-49 Senate majority. Lake plans to announce her candidacy at a 6:30 p.m. MT Tuesday (0030 GMT Wednesday) event in Scottsdale.
Lake, a former television news anchor at a Fox network station in Phoenix, ran in 2022 for governor, narrowly losing to Democrat Katie Hobbs. The Republican still has not conceded defeat, following former President Trump's practice of claiming falsely that his 2020 presidential election loss was the result of widespread fraud.
Lake is closely aligned with Trump, who so far leads the race for the 2024 Republican presidential nomination. In the past she has glowingly referred to him as "Superman."
Arizona shares around 370 miles (600 km) of its border with Mexico and immigration is sure to be one of the main topics in the Senate race. Some establishment Republicans have fretted that if she wins the nomination, her fiery, hard-right, election-denier stances might not sit well with some of the state's voters.
"There is an invasion at the Arizona border RIGHT NOW. Kyrsten Sinema and Ruben Gallego repeatedly voted AGAINST funding the border wall. They have rubber-stamped this open borders agenda. Arizonans are sick of it," Lake said on X, formerly known as Twitter, on Monday.
Lake joins a handful of Republican aspirants, including Mark Lamb, a sheriff in Pinal County, which is located between Phoenix and Tucson, and businessman Brian Wright.