Maine State Auditor Matt Dunlap is launching a Democratic primary challenge to Rep. Jared Golden (D-Maine), who has carved out a record as one of Congress’ most moderate Democrats as he has held onto a seat won by President Donald Trump for four terms.

While progressives have tried to capitalize on a wave of discontent with Democratic party leadership with primary challenges ahead of the 2026 midterm elections, Dunlap’s decision to run against Golden marks one of the first times a progressive has challenged a sitting swing-district Democrat. It is likely to be met by fierce resistance from House Democrats and others who believe only a candidate with a centrist track record like Golden has a chance of winning the rural 2nd District.

In launching his bid, Dunlap unveiled a progressive agenda, including support for Medicare-for-All, and attacked Golden for not doing enough to oppose Trump.

“I’m not OK with Donald Trump as president and that’s why I’m running for Congress,” he says in his debut ad, referencing a July 2024 op-ed where Golden said he was “OK with” a Trump victory.

Dunlap also noted he successfully sued the Trump administration in 2018 while serving as Maine’s secretary of state, forcing Trump to ultimately dissolve his “election integrity” commission.