Maine's Democratic House Speaker Sara Gideon says she's challenging veteran Republican U.S. Sen. Susan Collins, whose political future has generated an enormous amount of attention over the last year.
Gideon is a four-term state representative from Freeport who has been the speaker for the last two terms. Collins, first elected in 1996, is expected to run for another term but has yet to formally announce her candidacy.
Collins cruised to re-election in 2014 and has long been viewed as a moderate Republican. Liberals set up a fund to help try to unseat her after she voted to confirm President Donald Trump's Supreme Court selection Brett Kavanaugh last year. The fund has raised more than $4 million.
Gideon's website pledges to "put Maine First."
Progressive activist Betsy Sweet has also announced a run against Collins.