Rep. Joe Kennedy III (D-Mass.), the grandson of assassinated Sen. Robert F. Kennedy, has conceded defeat to incumbent Sen. Edward Markey (D-Mass.) in the Massachusetts Democratic Senate primary late Tuesday.
Polls closed around 8 p.m. EDT. With 43.99 percent of precincts reporting, Markey had 54.3 percent while Kennedy had 45.7 of the votes.
Massachusetts Democrats and Republicans were choosing nominees for nine U.S. House seats in addition to Markey's Senate seat.
Markey thanked his supporters for the win in an announcement on Twitter.
Speaking from his hometown in Malden, Markey told his supporters, "I spoke with congressman Kennedy just a few moments ago and I extended my respect and congratulations for a campaign that has been fierce at times but always fueled by a shared commitment to the people of this great commonwealth."
"We both love Massachusetts and the United States of America," he added. "I look forward to talking with congressman Kennedy and working with him to make the lasting, meaningful change that I know we are both committed to."
“Priority number one is to move Donald Trump from the White House," Markey said. "We must banish his agenda of division and destruction to the history books."
After conceding defeat, Kennedy told his supporters outside his campaign headquarters in Watertown that he would now work to help Markey's reelection.
“The senator is a good man. You never heard me say otherwise,” Kennedy said.
He said that his coalition of supporters "who do not have the luxury of accepting the status quo" will continue their fight for universal healthcare and civil rights improvements.
"We may have lost the final vote count tonight but we built a coalition that will endure," he said of his own campaign. “I would do this again with all of you in a heartbeat.”
The unsuccessful challenge makes it the first time a Kennedy has been defeated in a race for Congress in Massachusetts.
Markey appealed to voters in the deeply Democratic state by positioning himself as aligned with the liberal wing of the party. He teamed up with a leading progressive, Rep. Alexandria Ocasio-Cortez (D-N.Y.), on the Green New Deal climate change initiative—and at one point labeled Kennedy "a progressive in name only." Markey also received endorsements from Ocasio-Cortez and Sen. Elizabeth Warren (D-Mass.).
Kennedy, 39, had sought to cast Markey, 74, as someone out of touch after spending decades in Congress.
Markey will now face Republican Kevin O'Connor, an attorney, in the general election on Nov. 3.