BOSTON — As he seeks a second full term in the U.S. Senate, Democrat Ed Markey is facing a possible challenge from a member of the state’s most storied political family.

Democratic Congressman Joe Kennedy III, a grandson of Robert F. Kennedy, is floating the idea of challenging incumbent Markey in the 2020 Democratic primary, a move that has the state’s political pundits and observers buzzing.

Kennedy, 38, who is in his fourth term in Congress, has filed a statement of candidacy with the Federal Election Commission, but has yet to officially jump into the race.

He hasn’t set a deadline for a final decision on whether he will run, telling supporters last week in a Facebook post that he “hasn’t reached a decision yet.”

“I’m thinking about what I have to offer Massachusetts voters, what is most important in this political moment, and what kind of party Democrats need to be building for the future,” Kennedy wrote. “I hear the folks who say I should wait my turn, but with due respect — I’m not sure this is a moment for waiting.”

Kennedy didn’t directly criticize Markey, but suggested it might be time for a change.

“Our system has been letting down a lot of people for a long time, and we can’t fix it if we don’t challenge it,” he added.

Markey, 73, a Malden Democrat, was first elected to the Senate in 2013 after winning John Kerry’s former seat. He served decades in the U.S. House of Representatives prior to that.

Unlike Kennedy, Markey has been clear about his intentions to seek a second six-year term.

“I’m running straight out for the next year for re-election,” Markey told reporters Monday at the annual Labor Day breakfast in Boston. “I’m going to run on the issues that people want me to fight for and I have been fighting for on the Senate floor throughout my entire career: women, workers, climate change, gun safety protections — and I’m gonna continue to do that.”

A year out from the primary, many of the state’s all-Democratic congressional delegation have begun lining up behind Markey, including U.S. Sen. Elizabeth Warren, who is running for president.

“On the big issues facing Massachusetts, Ed is our greatest champion in the Senate,” Warren said in a recent YouTube video endorsing Markey’s re-election campaign.

Congressman Seth Moulton hasn’t taken a side in the possible Markey-Kennedy matchup but told reporters last week that he has spoken to Kennedy about his possible challenge.

“I think primaries are healthy for our democracy,” the Salem Democrat said at an event in Boston. “I wouldn’t be here without a without a primary.”

Moulton, a former Marine captain who ousted veteran Congressman John Tierney in the 2014 Democratic primary, said he recalls getting a lot of pushback from party officials.

“There were a lot of people in the Massachusetts Democratic establishment who told me, ‘Seth, not only are you going to lose this race,’ they said, ‘you’ll never be involved in Massachusetts politics again, because you dare to take on an incumbent,’” he said. “And of course that’s wrong.”

Markey also sought to stress his support among the state’s Democratic leaders, including Senate President Karen Spilka, D-Ashland and House Speaker Robert DeLeo, D-Winthrop.

Markey’s campaign has released a list of more than 100 current state senators and representatives who have endorsed his re-election bid — including Sens. Joan Lovely, D-Salem, and Barry Finegold, D-Andover, and Reps. Linda Campbell, D-Methuen, Paul Tucker, D-Salem, Frank Moran, D-Lawrence, Lori Ehrlich, D-Marblehead and Tom Walsh, D-Peabody.

Other challengers

Two other Democrats — Shannon Liss-Riordan, a labor rights lawyer, and Steve Pemberton, a former Walgreens executive — have already filed to challenge Markey in the primary.

Liss-Riordan has criticized Markey over his reluctance to support impeachment proceedings against Republican President Donald Trump following the release of Special Counsel Robert Mueller’s report.

“This country is stuck because of the cycle of Washington politics,” she said in a campaign video. “Washington needs a fresh voice willing to break that cycle.”

As of the end of June, Markey reported having more than $4 million in his campaign account, according to his filings to the Federal Election Commission.

Kennedy had $4.2 million in his 4th Congressional District account as of June 30, his FEC filings show, which could be transferred to his Senate campaign account if he chooses to run.

Liss-Riordan had raised about $1 million as of June 30, while Pemberton — who entered the Senate race at the end of July — hasn’t reported any fundraising activity.

Forcing a choice

Political observers say Kennedy’s challenge could divide Democratic voters, who would be forced to choose allegiance between two popular party stalwarts.

“It would force Democratic voters to choose between two people they like,” said Erin O’Brien, a professor and chairwoman of the political science department at the University of Massachusetts at Boston. “Democrats seem to really like having both Markey and Kennedy in the state’s congressional delegation.”

Despite Kennedy’s name recognition, O’Brien suggests he wouldn’t face an easy road trying to unseat Markey, who has a lot of support among progressives in the party.

“People like Joe Kennedy, but he just doesn’t have the legislative record that Ed Markey does,” she said. “That said, it’s hard not to notice that the Kennedy name, especially for the Senate, holds bar in Massachusetts.”

Jeffrey Berry, a political science professor at Tufts University, said he believes Markey is vulnerable to a challenge and Kennedy would have the advantage if decides to run.

“He’s a young congressman, with strong name recognition, who could energize the Democratic base,” he said. “Would he win? I don’t know. But he’s certainly a credible contender.”

Christian M. Wade covers the Massachusetts Statehouse for the North of Boston Media Group’s newspapers and websites. Email him at cwade@cnhi.com

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