WASHINGTON (AP) — Massachusetts Democrats will decide the latest head-to-head matchup between the party’s moderate and progressive wings in a state primary Tuesday, but this time, top progressives are backing the incumbent against a more moderate challenger.U.S. Sen. Ed Markey faces a competitive Democratic primary challenge from U.S. Rep. Seth Moulton in his bid for a third full term. The contest ties together two recurring themes in Democratic primaries this year: progressives vs. moderates, and longtime incumbents vs. significantly younger challengers.Bay State voters will also choose nominees for U.S. House, governor, and a variety of state and local offices.Markey, who turned 80 in July, is the second-oldest sitting U.S. senator seeking reelection in 2026. He took the seat in 2013 after serving nearly 37 years in the House. He last faced a competitive primary in 2020, when he defeated then-U.S. Rep. Joseph Kennedy III, 55% to 45%.

Moulton is a six-term congressman who briefly sought the 2020 Democratic presidential nomination. He will turn 48 in October.Markey has had a slight financial advantage over the course of the campaign, raising and spending more than $8 million compared with more than $6 million for Moulton. Moulton had a slight advantage in cash-on-hand as of Aug. 12.A majority of delegates to the state party convention in May voted to endorse Markey for reelection, but Moulton won enough support to qualify for Tuesday’s ballot. Markey’s other key backers include U.S. Sen. Elizabeth Warren of Massachusetts, as well as U.S. Sen. Bernie Sanders of Vermont and U.S. Rep. Alexandria Ocasio-Cortez of New York.