Bernie Sanders

US Senator Bernie Sanders on Monday endorsed Senator Ed Markey in his reelection bid against US Representative Seth Moulton, calling the 79-year-old incumbent “one of the strongest progressive voices” in the Senate.

Sanders’s support for Markey may be unsurprising given the dynamics in this year’s contest: Moulton, 47, is largely viewed as a more centrist Democrat, while Markey’s 2020 reelection victory cemented him as a progressive icon in the eyes of many Democrats.

But Sanders, one of the defining characters of the modern progressive movement, passed on endorsing in the 2020 primary that pitted Markey against then-Representative Joe Kennedy III.

Sanders’s endorsement also comes as Moulton has embraced more progressive positions on the campaign trail. He’s called to “abolish ICE” and returned money donated to him by AIPAC, a pro-Israel group. The Salem Democrat has also looked to paint himself as a candidate with “a bold, progressive agenda” who will bring “progressive change” to the Senate.

In a statement released by Markey’s campaign, Sanders said Markey “has been an ally in taking on the billionaires, Big Tech, Wall Street and Private Equity as they continue to try to take over every aspect of our lives and further corrupt our government.”

“He knows which side he’s on,” the Vermont senator said.

Markey’s supporters have sought to make the primary a test of progressive credentials. A super PAC backing the incumbent launched an ad campaign this year targeting Moulton’s record on issues, including immigration enforcement and the Green New Deal, casting him as insufficiently progressive.

Sanders’s endorsement is likely to bolster that message, adding to the list of high-profile progressive supporters backing Markey, including US Senator Elizabeth Warren, Boston Mayor Michelle Wu, and US Representative Ayanna Pressley.

At the same time, the endorsement from the 84-year-old Sanders could help Moulton. He has railed against the so-called gerontocracy in Washington, and could seek to cast the endorsement as reinforcing his central argument that Democratic voters are looking for generational change.

Sanders has endorsed several younger candidates and non-incumbents in other states, to some success so far this cycle. He backed Graham Platner’s successful bid for the Democratic nomination in Maine’s Senate primary, as well as candidates in New Jersey, Montana, Ohio, Pennsylvania, and New York.

In his own statement Monday, Markey praised Sanders for “speaking truth to power and standing up for working people against entrenched corporate interests.”

“At a time when working families are being squeezed by rising costs and billionaire special interests are exerting more influence than ever, we need leaders who are willing to take on powerful interests and deliver real results,” he said. “That’s exactly what Bernie has done throughout his career, and it’s what I will continue to do for the people of Massachusetts.”

Kelly Garrity can be reached at [email protected].