Arizona representative Martha McSally told her Republican colleagues that she plans to launch a run for Senate in 2018, according to the Arizona Republic.
A run from McSally has been anticipated since the announcement by Sen. Jeff Flake (R., Ariz.) that he would not be running for reelection next year. McSally, an Air Force veteran, was first elected to the House of Representatives in 2014.
McSally would immediately become the highest profile challenger to Republican Kelli Ward, who had already planned to challenge Flake in the party's primary.
Democrats in the state immediately set their sights on McSally, calling her a member of Senate majority leader Mitch McConnell's "establishment."
"Mitch McConnell's Martha McSally—who has already earned the ire of conservatives—will take up the same establishment campaign that forced Sen. Jeff Flake to sprint out the door, and this attempted coronation will only continue the GOP civil war in Arizona," said the Arizona Democratic Party, according to the Republic report.
The Senate Leadership Fund, a super PAC linked to McConnell, predicted immediately after Flake's retirement announcement that Ward would not end up being the Republican nominee in 2018.
"The one political upshot of Sen. Flake's decision today is that Steve Bannon's hand-picked candidate, conspiracy-theorist Kelli Ward, will not be the Republican nominee for this Senate seat in 2018," said the Senate Leadership Fund in a statement.
The announcement by McSally leaves Republicans without a clear candidate to run against Democrats in Arizona's Second Congressional District. Democrat Ann Kirkpatrick, a former congresswoman who ran unsuccessfully against Republican senator John McCain in 2016, has already moved across the state into the district to challenge McSally and appears to be the choice of Democrats in Washington, D.C.