Seth Moulton

U.S. Rep. Seth Moulton continues to narrow the gap in his Democratic primary contest with U.S. Sen. Ed Markey, closing to within 6 points of the veteran lawmaker in a new poll.

Markey, D-Mass., leads Moulton 41%-35% in the latest University of New Hampshire poll. Moulton, D-6th District, trailed Markey by 13 points in a similar UNH poll in April.

Moulton trailed Markey by 17 points in a Boston Globe/Suffolk University poll in April and by 5 points in an Emerson College poll in May.

Support for Markey, who’s been on Capitol Hill since the Carter administration, dipped from 46% to 41% between those April and July UNH polls. Meanwhile, the share of undecided voters increased, from 15% in April to 23% in the new poll.

In a statement, Moulton’s campaign said the latest result, nearly a statistical dead heat, "underscores a massive shift in momentum" in the closely watched primary campaign.

UNH pollsters sampled the opinions of 623 likely voters between June 18 and June 23. The margin of error for that sample was 3.8%.

Moulton, a 47-year-old Marine veteran who has made generational change on Capitol Hill the animating force of his campaign, took majority support among self-identified moderates (70%) in the new poll.

Markey, 79, who has racked up endorsement after endorsement from elected officials across the state, locked up the support of self-identified liberals (51%), progressives (52%) and socialists (67%).

A plurality of likely primary voters (48%) said they had a favorable opinion of Markey, compared to 32% who said the same thing about Moulton.

Eighteen percent of those same voters said they had an unfavorable opinion of Markey, compared to 27% who said they were neutral about him.

Twenty percent said they had an unfavorable opinion of Moulton, while 27% were on the fence about the North Shore pol.

The Democratic primary is Sept. 1. The winner faces Republican John Deaton in the November general election.