Congressman Joe Kennedy, long seen as a rising star, crashed to defeat Tuesday in his bid for a US Senate seat, the first time the storied American political dynasty lost a state election in Massachusetts.
Incumbent Senator Ed Markey, a political veteran who re-cast himself as the fiery liberal in the race, harnessed the state's progressive energy to handily turn back a primary challenge from Joseph Kennedy III, the grandnephew of assassinated president John F. Kennedy.
The 39-year-old Kennedy said he called Markey "to congratulate him and to pledge my support" in the months ahead."
With votes still being counted, Markey was leading around 55 percent to 44 percent.
The race pitted two well-liked progressives against each another, but it was Markey's organizational energy and appeal to the ascendant left that won out over Kennedy.
"Tonight is more than just a celebration of an election, it is a celebration of a movement," Markey wrote on Twitter.
Representative Alexandria Ocasio-Cortez, a figurehead of the party's progressive wing, congratulated Markey on the win.
"Yours is a victory for the progressive movement, for 21st century policy, and for the Green New Deal," she wrote on Twitter.
The Green New Deal, an economic plan to tackle climate change, was co-authored by Markey and Ocasio-Cortez.
Since he is not allowed to be on the ballot as a candidate for both the House and Senate, Kennedy is not running for re-election to his House seat. Come January, there will be no one from the Kennedy clan in elected office.
The grandson of slain attorney general Robert F. Kennedy is part of the family's fourth generation to carry the political torch, entering the House of Representatives in 2013.
"Every race I've ever run, I've made it clear it's me on the ballot," Kennedy told AFP as he stumped for 11th-hour votes Tuesday in Boston.
After his loss he told supporters that together they "built a campaign for working folks of every color and creed, who carry the economic injustice of this country on their backs."
At 74, his rival Markey is a generation apart, a progressive political workhorse who spent 37 years in the House before rising to the Senate in 2013.
He led Kennedy in recent polling and was able to seal the deal with strong support in Boston and college towns such as Amherst.
For the Kennedy clan, there was much on the line. For all but two years since 1947 -- nearly a third of the history of the United States -- a Kennedy has served in elected office.
They are the quintessential American dynasty, one of the closest things the country has to royalty.
Like his presidential great-uncle, the lanky, red-haired Kennedy ran on the promise of a new generation.
And he had received the rare endorsement of House Speaker Nancy Pelosi, who in 2018 appointed him to deliver the Democratic response to President Donald Trump's State of the Union speech.
Markey, who framed his candidacy on a liberal, anti-establishment platform, has powerful supporters apart from Ocasio-Cortez, including Senator Elizabeth Warren.
He is virtually assured victory in November's general election; only two Republicans have won US Senate seats from Massachusetts in the last half-century.
The Democratic National Convention last month hinted that the Kennedy clan may still have a political future when it aired a video message from JFK's daughter Caroline Kennedy and her 27-year-old son Jack Kennedy Schlossberg.
"We can reach these new frontiers, but only with a president who asks what he can do for our country," Schlossberg said, echoing his grandfather's 1961 acceptance speech when he famously said: "Ask not what your country can do for you."