The prototypical Democrat vulnerable to a primary this year has been old, in Washington a long time, and vulnerable from the left.

But in Massachusetts, there’s a race that’s scrambling that formula. Sen. Ed Markey is 80, and he’s been in Congress for 50 years. But he’s been a stalwart ally of progressives; he was, for instance, the main Senate champion of the “Green New Deal.” And the leaders of the Democrats’ left flank, like Sens. Bernie Sanders and Elizabeth Warren, are swinging into action to try and defend him. “It’s not your age, it’s the age of your ideas. And in this race, I’m the youngest guy,” Markey has said.

His opponent, Seth Moulton, a 47-year-old Marine Corps veteran, also goes against type. While “moderate” and “establishment” often are treated as synonyms, Moulton has a history of pushing back against both progressive activists and older Democratic leaders. In his current run, he’s made generational change his main issue, including some blunt warnings about Markey’s age. 

“If Democrats win the Senate, it will almost certainly be by one vote, and we can’t afford to lose that vote due to a medical absence or emergency,” Moulton told me in an interview. “That’s not ageism, that’s just actuarial tables.”

But his Senate campaign isn’t the first time he’s taken on Democratic leaders. In 2018, he led a (failed) effort to stop Nancy Pelosi from becoming speaker again, arguing again that the aging House leadership needed to clear a path for younger members. In 2024, he became one of the first prominent Democrats to bail on President Joe Biden after his disastrous debate, saying the president needed to “let new leaders rise up.”

The party establishment, Moulton told me, has “failed to be honest with the American people about the challenges we face.” He cited Democrats denying there was “an immigration problem at the southern border under Biden,” their insistence that Biden-era inflation was “transitory,” and their initial defense of Biden after the debate exposed his frailty.

Some of his criticisms of the party have rankled progressives. After President Donald Trump’s victory in 2024, he publicly criticized Democrats’ stance on trans athletes in stark terms, telling the New York Times he didn’t want his “two little girls” getting “run over on a playing field by a male or formerly male athlete” — a statement that earned him intense backlash in Massachusetts. 

Now facing a Democratic primary electorate in a very liberal state, Moulton has tried to avoid being pigeonholed as a centrist. For instance, he said he supports abolishing ICE and prosecuting many of its officials, and he said he supports legislation like the Transgender Bill of Rights. Asked about his comments on transgender youth, he told me his intention “was not to hurt or offend anybody, but to say that we need to be willing to have these tough conversations as Democrats — and not simply cede this territory to Republicans.”

Instead, his principal argument has been that Markey should pass the torch — and that frustrations with what congressional Democrats’ ineffectiveness should in part be aimed at Markey. 

“One of the first votes I’ll take in the Senate will be against Chuck Schumer for leader,” Moulton said.

Markey, for his part, has accused Moulton of throwing trans kids “under the bus” and argued his own long record and support for causes from climate to Medicare-for-all shows him to be a reliable progressive ally. 

“Congressman Moulton is trying to walk a political tightrope,” Markey campaign manager Cam Charbonnier told Vox. “He’s working to appeal to moderate voters, but that coalition alone isn’t enough to win a Massachusetts Democratic primary. So, he’s also trying to appeal to progressives, but he doesn’t have the track record to back that up. The result is a campaign that’s trying to be everything to everyone, leaving voters questioning what he actually stands for.”

Polling in the race has been sparse, but the last two public surveys both showed a surprisingly close race ; Markey led by just 5 points in one and 6 in the other. However, there were many undecided voters, and we’ll soon see whether ad campaigns — like Markey’s new one featuring Sanders, Warren, and Rep. Ayanna Pressley — shift the numbers.

If Moulton wins the September 1 primary, or even comes close, it would suggest that the Democratic base’s frustrations with gerontocracy and Washington are more than stand-ins for a debate over ideology and reflect broader concerns about older politicians losing touch, being ineffective, aging, and even dying in office.

But if Markey ends up sailing to victory, it would send a message that it can be perilous for upstart Democratic challengers like Moulton to break with the progressive base — and that validation from the Sanders wing of the party can be a very valuable thing.

Sen. Ed Markey beat back a previous primary challenge by mobilizing progressives

Though Markey entered the House of Representatives 50 years ago, his team argued that his record shows he was frequently on the right side of history — that, for instance, he started focusing on climate change as far back as the 1980s and that he supported same-sex marriage in the 1990s. (Moulton bristled at this a bit, telling me, “He was elected as a pro-life Democrat who was opposed to the racial integration of Boston schools.”)

In 2009, he and Rep. Henry Waxman co-authored Democrats’ sweeping “cap-and-trade” climate bill, which was one of President Barack Obama’s top priorities. The bill, which became colloquially known as Waxman-Markey, died in the Senate.

When Sen. John Kerry joined Obama’s Cabinet as secretary of state, Markey ran for his open Senate seat. He was the more progressive candidate in a primary against Rep. Stephen Lynch, which he won by 15 percentage points.

But toward the end of Markey’s first full Senate term, an ambitious Democrat with a famous name — then-Rep. Joe Kennedy III, grandson of RFK (and nephew of RFK Jr.) — launched a primary bid against him, also with a message of generational change.

Markey’s initial polling was quite weak, he still wasn’t very well-known in the state, and he appeared to be in serious danger. But, unexpectedly, he became an online phenomenon of sorts, as young progressives, impressed by his Senate push for the Green New Deal and early endorsement from Rep. Alexandria Ocasio-Cortez (who has not weighed in this time), rallied to his side. His campaign’s message that he was a movement champion proved successful, and he ended up winning the primary by 11 points.

When Democrats had a trifecta in Washington again under President Joe Biden, they passed their climate bill. The new law, the Inflation Reduction Act, established the Greenhouse Gas Reduction Fund, a “green bank” of sorts. The concept, in various iterations, had been one of Markey’s main causes over the years, and its enactment was a major achievement. Yet, that success was short-lived, as the Trump administration is now attempting to dismantle the program.

Rep. Seth Moulton has been a thorn in the Democratic establishment’s side

Moulton, for his part, believes he can take down Markey, because he took down a long-time Democratic incumbent once before; that’s how he got his start in politics.

Rep. John Tierney had represented his northeastern Massachusetts district for nearly two decades, when Moulton challenged him in a 2014 primary. A longtime ally of Nancy Pelosi, Tierney became vulnerable due to a gambling scandal involving his family. (His wife’s brother was accused of racketeering for operating an illegal offshore casino, and Tierney’s wife was accused of preparing false tax returns. Both were convicted and sent to prison.)

In contrast, the 35-year-old Moulton was a fresh face — a Harvard grad and a decorated combat veteran who had served four Marine Corps tours in Iraq. He proved an effective fundraiser and campaigner, upsetting Tierney by 10 percentage points.

Yet, Moulton quickly grew frustrated with Washington. After Democrats’ 2016 defeat, he became one of the party’s most outspoken critics of Pelosi. Already, by 2017, there was talk he might run for president — and ample anonymous quotes from other Democrats disparaging him as opportunistic, grasping, and disloyal.

Moulton insisted throughout that he was making a case that went beyond personal ambition. Before the 2018 midterms, he started the Serve America PAC to try and elect more members with military or national service backgrounds who were skeptical of Democratic leaders — more people like him — to Congress. But when Democrats retook the House majority, Moulton’s high-profile effort to supplant Pelosi flamed out. 

So did his subsequent presidential bid. He was in the race for four months in 2019 but dropped out when he failed to qualify for debates, warning Democrats on his way out against “veering too far left” in their choice of candidate. 

But the latest round of Democratic failures — Biden’s debate face-plant and Kamala Harris’ defeat — spurred Moulton to make another attempt at higher office. 

“Someone who has been in Congress for half a century and will be 86 years old at the end of his next term is, in fact, too old,” Moulton told the Washington Post after launching his campaign last October. “If we haven’t learned the lessons of Ruth Bader Ginsburg and Dianne Feinstein and Joe Biden…then where are we going as a party?”

Is this a race about who’s the best progressive, or about who wants to shake up the way things are done?

In addition to the close polling in recent months, Moulton’s fundraising has been impressive — aided, Markey’s allies argued, by donors associated with private equity and crypto. (A pro-Markey Super PAC has fundraised heavily from unions, as well as some investors and corporate executives.)

But when Markey and Moulton faced off on the debate stage earlier this month, nothing even close to the Joe Biden catastrophe ensued. Markey insisted he’d never been more energized, and both candidates hit their preferred messaging points. For Markey, that meant portraying himself as a dependable progressive and Moulton as an unreliable ally.

“After the 2024 election, Congressman Moulton decided that he was gonna throw trans kids under the bus — the political bus — and blame them for the loss of the 2024 election.” Markey said. “Those kids are vulnerable. Those kids need love. Those kids don’t need to be scapegoated and blamed for what was wrong with the Democratic Party.”

But in Moulton’s interview with me, he said that “it’s very hard to find any fundamental differences in the issues” between him and Markey. 

“I’m an ally for all the people and causes on all these issues that Senator Markey and I agree on, and I’m very proud of how much my voting record aligns with Senator Markey’s on the major issues,” Moulton said. “But I’m not gonna just sit back and do what the establishment tells me to do, especially when the establishment is failing.”

Source: Vox.