Moulton is confident that he’ll get enough delegate votes at this month’s convention to make the primary ballot. Last week an Emerson Poll put Markey at 37% and Moulton at 32% among primary voters, with Markey winning Democrats and Moulton winning the “unenrolled” independents who can pull a Democratic ballot. Markey’s team disputed those numbers.

Markey, who turns 80 in July, waged a remarkable 2020 campaign that recast him as a progressive hero and dealt the Kennedy family its first real electoral defeat in Massachusetts.

Moulton did not strike Democrats as a Kennedy-level challenger. He ran quixotically for the 2020 Democratic presidential nomination, and after Kamala Harris’s defeat, he drew protests after criticizing the party’s position on trans participation in girls sports.

“I have two little girls. I don’t want them getting run over on a playing field by a male or formerly male athlete,” he told the New York Times. Three days after Moulton announced his Senate bid, Markey spoke at the October No Kings march in Boston with a pink, white, and blue transgender flag draped over his shoulders.

Moulton has said since that he does not support categorical bans on transgender athletes’ participation in girls sports. In a recent interview with Semafor he emphasized his support for the “Transgender Bill of Rights,” a House bill co-authored by Markey that extends protections under the Civil Rights Act of 1964 to gender identity, and codifies non-discrimination in housing, credit, education and employment. He said that he wanted his party to come up with a positive rights agenda, recalling a father of a trans child who thanked him for “actually having the courage to take on these issues” when other Democrats repeated talking points.

Progressive endorsers stuck with Markey, but Moulton has found considerable interest in his generational change message – more than in 2020, when Democratic voters were nominating Joe Biden for president and hoping that Ruth Bader Ginsburg could-out last the Trump administration.

Markey is running a less aggressive race than he did six years ago. As of April 1, he had raised less than $3.7 million for re-election, with $2.5 million on hand; he had $4 million on hand at the same point in 2020. Moulton had raised $4.1 million, with $3.3 million on hand.

That’s a smaller cash advantage than Joe Kennedy III built in his Markey challenge, but the senator has not found another re-election argument as crisp as his last one. In 2020, he touted his co-authorship of the Green New Deal and his alliance with Rep. Alexandria Ocasio-Cortez. They have not re-introduced a version of the environmental package, and Ocasio-Cortez, an early endorser in 2020, has stayed neutral. The Trump administration’s gutting of the climate funding Markey did get from Biden has deprived him of an accomplishment to run on.

The lower-key campaign was on display last week in Gloucester, when both men addressed local Democrats. Moulton arrived early, shaking hands at every table, and delivered a short speech.

Markey waited outside the venue until his time to speak. The crowd’s biggest applause came when he said he was “number one in voting against more of Donald Trump’s nominees than any other member” and that he was “the first United States senator to call for the abolition of ICE.” He described his “AI Civil Rights Act” that would enforce “protections against discrimination against women, against minorities, the LGBTQ community.”

“That was the first time I’d heard of it,” Moulton told Semafor. After posing with local high school scholarship winners, Markey headed out.