Joe Miller, a tea party favorite, filed paperwork to formally enter the U.S. Senate race in Alaska.
Mr. Miller is hoping to oust Democratic Sen. Mark Begich, who won the seat from Ted Stevens in 2008 but is now considered vulnerable.
He filed his statement of candidacy with the Federal Election Commission, which gives him the ability to start raising money for his campaign, USA Today reported.
Mr. Miller won the 2010 Republican primary against Sen. Lisa Murkowski — one of a number of tea party-backed candidates who defeated establishment Republican politicos.
He was backed by Sarah Palin during that campaign — but Ms. Murkowski went on to win her reelection bid as a write-in candidate, USA Today said.