Incumbent, 80, beats back challenge from Seth Moulton, who argued Markey was too old to be effective at his job

Senator Ed Markey won the Democratic primary in Massachusetts on Tuesday, beating back a challenge from Seth Moulton, a congressman who tried to unseat him by arguing to voters his opponent was too old to be effective at his job.

Massachusetts is heavily Democratic, making the senator favored to win a third full term in the November general election, where he faces the Republican nominee, John Deaton.

Markey, looking to clinch another Senate term, leads younger rival Seth Moulton in blue state’s primary poll

Democrats have spent the summer ousting long-serving incumbents in primaries across the country. On Tuesday, Massachusetts voters will decide whether that generational revolt extends to the 80-year-old Ed Markey, whose younger Democratic rival has argued that the incumbent is simply too old to serve another term.

But the Senate primary in this heavily Democratic state flips a central dynamic of previous contests, where youthful progressive insurgents have targeted – and in several cases, toppled – older incumbents they derided as avatars of an outmoded cautious establishment.