Washington (CNN) - Republican Sen. Jim DeMint announced his endorsement of Washington Senate candidate Dino Rossi on Thursday.
The move is the latest in a series of endorsements made by the South Carolina senator, many of which have pitted him against either the GOP establishment or former Alaska Gov. Sarah Palin.
"Dino Rossi is a principled conservative who will help us take our country back. He will fight to stop the massive spending, bailouts, and debt that are bankrupting our country," DeMint said in a statement. "Dino understands the stimulus bill was a failure, he will fight to repeal the health care takeover, and he will help us pass a constitutional amendment to balance the budget.
Rossi and two other Republicans, Clint Didier and Paul Akers are in the battle to challenge incumbent Democratic Sen. Patty Murray.
Palin, another prominent Republican who has a full stable of endorsed candidates, backed Didier, a Tea Party favorite and former professional football player with the NFL's Washington Redskins earlier this year.
The 2010 bid is Rossi's third run for statewide office in Washington. He ran for governor in 2004 and 2008.
Washington is the only state in the nation to hold a non-partisan primary, with the top two vote-getters advancing to the general election.
Earlier this year California voters passed a referendum that would move the Golden state towards a similar system.
– CNN's Paul Steinhauser and Peter Hamby contributed to this report