How did Ed Markey defeat a Kennedy in Massachusetts? Easily, as it turns out. Joe Kennedy called to concede a double-digit defeat in the Senate primary after starting out looking like the vanguard of the next dynastic generation. Instead, he became the first Kennedy to lose in Massachusetts:

Sen. Edward J. Markey triumphed in the toughest fight of his near 45-year Capitol Hill career Tuesday, making Rep. Joseph P. Kennedy III the first member of the Kennedy dynasty to lose a Massachusetts election.

Markey, 74, won the Democratic Senate primary by rallying progressive Democrats to his cause and contrasting his own working-class roots with those of an opponent whose namesake and great-grandfather, Joseph P. Kennedy Sr., groomed his son John F. Kennedy to be president and sons Edward M. and Robert F. — the 39-year-old candidate’s grandfather — to be senators.

Markey, who trailed by double digits in early polls, was leading Kennedy 55 percent to 45 percent when The Associated Press called the race at 10:30 p.m. Eastern time.

How bad did Kennedy blow this? He lost Boston, much to the amazement of MSNBC analyst Steve Kornacki. Markey managed to make the Kennedy legacy an albatross by tackling it directly, Kornacki also notes, almost scornfully reflecting on JFK’s most famous quote in a campaign ad:

This may be one of the most humiliating political defeats seen since Richard Nixon lost his gubernatorial run in 1962. Don’t forget that the national party had tried to leverage the Kennedy name and lift Kennedy to national status just two years ago, which no doubt encouraged the congressman to seek Markey’s Senate seat. Democrats assigned Kennedy the role of official response to the State of the Union address in 2018, which didn’t exactly wow observers but definitely make Kennedy look like their choice for rising star.

So what happened? Kennedy started out with polling that showed him nearly twenty points out in front of Markey, The Hill notes, but Markey simply out-hustled and out-progressived his young challenger:

The incumbent senator’s victory comes nearly a year after Kennedy, 39, entered the race with a double-digit lead over the 74-year-old incumbent senator, drawing media attention from Massachusetts and beyond.

A Change Research survey conducted in August 2019 before Kennedy announced his candidacy showed the congressman with a whopping 17-point lead over Markey. …

Markey benefited from widespread support from major progressive groups ranging from the Sunrise Movement to MoveOn to Our Revolution. He also garnered the backing of progressive leaders such as Rep. Alexandria Ocasio-Cortez (D-N.Y.), fellow Massachusetts Sen. Elizabeth Warren (D) and activist Ady Barkan.

Progressives celebrated Markey’s win on Tuesday, adding it to the list of primary wins this summer.

“Before tonight, a Kennedy had never lost an election in Massachusetts. But even a 100 year dynasty can not overcome the Green New Deal,” the Sunrise Movement tweeted.

More like a 70-year dynasty, but whatevs. Kennedy seemed determined to blow this chance almost from the beginning, having nearly no policy differences with Markey but trying to cast himself as an anti-establishment candidate. As I wrote at the time, even Kennedy-besotted Massachusetts voters couldn’t swallow that whopper:

The Kennedys are the system and the establishment, especially in Massachusetts. His grand-uncles held the state’s other Senate seat for most of 50 years, and his family members have held seats in the House for longer than that. (JFK won the dynasty’s first House seat in 1946.) If the system has been “letting people down for a long time,” then Kennedys have been part of the problem rather than the solution.

That brings up another point. If Kennedy has “ideas” on how to fix the “system,” why hasn’t he done anything with them? He’s been in the House for four terms, and has the advantage of being in the majority in this session. If he can’t advance those ideas in the House, what makes the Senate so special, especially since it’s controlled by the Republicans? Kennedy hasn’t been waiting for his turn, he’s gotten it four times already.

Now that Kennedy has done the unthinkable for a Kennedy in Massachusetts — lose — what’s next? He could wait for Markey to retire, which is what Kennedy should have done in the first place, but now he looks like an ambitious fool. Nixon came back from a humiliating defeat too, but Nixon had actual accomplishments for a springboard. Kennedy has been a dilettante for four terms in the House, doing nothing with his time except apparently looking for the earliest opportunity to make the family’s claim on a Senate seat.

Democrats will likely still try to leverage the Kennedy name and get him elected to something soon. Joe III is still probably their best bet when Markey does retire, but … he’s not going anywhere on his own steam or on his family’s name for a while. And that truly is something new in Massachusetts for a Kennedy.