By Jon Keller

BOSTON (CBS) – The Democratic US Senate primary debate Sunday night between Massachusetts Rep. Joe Kennedy and Sen. Ed Markey underscored a fundamental political truth – races involving an incumbent tend to be a referendum on that incumbent.

So it’s no surprise that Markey’s voting record and public presence across the state were once again Kennedy’s prime targets in the debate co-sponsored by NBC10, Telemundo and NECN. But it was surprising how much Markey continues to struggle to deflect Kennedy’s attacks (not to mention those of some of the debate questioners) and transition from defense to offense.

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For example, one of Markey’s significant legislative accomplishments has been his work to find better treatments for Alzheimer’s disease, among the most widespread, frightening and costly health issues of our time. He co-wrote the National Alzheimer’s Project Act, and the advocacy group US Against Alzheimer’s calls Markey “one of Alzheimer’s strongest champions in Congress.”

One of Markey’s best moments in a climactic 2013 WBZ-TV Senate debate with Rep. Stephen Lynch was his emotional story of how his mother’s own struggle with the disease inspired him to make finding a cure a career-long crusade. But Sunday night, unless I made a fridge run and missed it, he did not find a way to mention the issue, squandering an opportunity to connect with worried voters, showcase his personal story, and rebut the persistent claim that because he mostly lives in a DC suburb he has lost touch with local concerns.

Instead, Markey repeatedly defended himself by citing endorsements from other politicians, at one point crowing that within Kennedy’s Fourth Congressional District, “nineteen of the state representatives and state senators are endorsing me, only four who know him best… are endorsing him.”

State rep and senator endorsements? Really? I’m guessing these are not the most direct route to a voter’s heart these days, or ever for that matter. Scads of Massachusetts pols endorsed Sen. Elizabeth Warren for president (including Markey and Kennedy) and she finished a dismal third in the state primary.

And Markey’s endorsement fixation teed Kennedy up for his bet line of the night.

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“This is why we need change,” he said, with the somber tone of a son addressing siblings on the need to take an aging dad’s car keys away. “Because it is a Washington thing to think that endorsements of elected officials means credibility and means success. That is the politics of the past and it does not work.”

Establishment endorsements didn’t help longtime incumbent Congressman Mike Capuano hold off his 2018 primary challenge from Ayanna Pressley, and that has from day one been the template for Kennedy’s challenge. If anything, these endorsements insult voters and the street-level activists who will ultimately get the vote out by placing outsized importance on some big-wig’s blessing. They infect the endorsee with whatever negatives or enemies the endorser may have. And they hang the recipient with an adjective no one at this moment in time should want: establishment candidate.

Markey’s diligent campaigning in an extremely difficult pandemic environment has helped dispel any notion that he feels reflexively entitled to another Senate term. He’s doing his best to earn it.

But if he loses narrowly, Markey may look back with regret on another blunder – his campaign’s failure to reign in the entitlement complex of his supporters. Initially, Kennedy’s public deliberations over jumping into the race were met with disgusted cries of “wait your turn,” not a very marketable slogan at a time when so many are marching in the streets to demand change now. (Remember Pressley’s campaign slogan? “Change Can’t Wait.”)

And lately some pro-Markey Twitter trolls have taken to smearing the Kennedy family online, a truly dumb move in a state where solid majorities say they have a favorable view of the Kennedys. And as he’s done since his first run for Congress in 2012, Joe Kennedy has played down the legacy angle by keeping his family references to a minimum and shunning celebrity Kennedy campaign appearances. He doesn’t need to draw the connection – it’s on his yard signs and all over his face.

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We’ll see if any of these dynamics change when the two men meet in their next debate in the WBZ-TV studios on Tuesday, August 11 at 7 p.m., with yours truly moderating. Your issue-oriented questions for the candidates are welcome at

Jon Keller