Massachusetts Governor Maura Healey endorsed Maine Governor Janet Mills in her bid for the US Senate on Tuesday, weighing in on one of the most closely watched races of the 2026 election cycle.
Healey is backing Mills in the Democratic primary over Graham Platner, a progressive candidate endorsed by Senator Bernie Sanders of Vermont. The winner of the primary is expected to face Republican Senator Susan Collins, who is serving her fifth term and is widely expected to announce a run for a sixth term next year.
“I am proud to endorse Janet,” said Healey in a video released on X, the social media platform. “She’s the only candidate in the race with a proven record of standing up to bullies like Donald Trump.”
The endorsement is unlikely to come as a surprise. Healey and Mills share similar political profiles: both are moderate Democrats who previously served as state attorneys general and are also the first women to be elected governor of their respective states. They have worked together on issues including energy policy, health care costs, abortion rights, and Trump-era tariffs that have affected New England’s trade with Canada. Mills also tapped Healey’s political network early in her campaign, sending a fundraising appeal to Healey’s email list shortly after entering the race in October.
Healey hosted a fundraiser for Mills last week in Boston.
“Governor Healey and I have been fighting for the people of our states for years, standing up to those who would do them harm and delivering real results for working families, including expanding access to health care and defending abortion rights,” Mills said.
The endorsement is not Healey’s first foray into politics beyond Massachusetts. She was actively involved in last year’s presidential campaign, attended a fundraiser for the Democrat who won New Jersey’s gubernatorial race this fall, and has campaigned multiple times in New Hampshire on behalf of Democratic candidates.
James Pindell is a Globe political reporter who reports and analyzes American politics, especially in New England.