BOSTON — Lowell is the most populous city in the sprawling 3rd Congressional District and historically plays an oversized role in determining who the region sends to Congress.

Three of the recent Democrats who've represented the district — the late Paul Tsongas, Marty Meehan and most recently Niki Tsongas — were Lowell natives or residents. The Spindle City, with its 110,000 residents, is traditionally a key battleground that candidates must win, political observers say.

But as a field of challengers to replace outgoing Rep. Niki Tsongas begins to take shape, the intensity of interest among political hopefuls is shifting noticeably northward.

Three of the eight Democrats testing the waters for a potential run have roots in Andover and are expected to use the town as a base to run.

State Sen. Barbara L'Italien, a Democrat who grew up in Andover, is among them. She lives in an Andover precinct just outside the congressional district but represents other communities in the district, including Lawrence and Dracut.

Dan Koh, a former chief of staff for Boston Mayor Marty Walsh, and Nadeem Mazen, a Cambridge city councilor, also have formed exploratory committees.

Koh recently moved back to Andover to run; Mazen has filed to run using his parents’ address and is expected to move back to town.

The only person from Andover to represent the district in Congress was Republican Paul Cronin, who held the seat from 1973 to 1975 after Lowell Republican F. Bradford Morse was named under-secretary general of the United Nations.

Steve Kerrigan, a Lancaster Democrat and 2014 nominee for lieutenant governor, is also considering a bid for the Democratic nomination. Haverhill Mayor Jim Fiorentini is expected to run.

North Andover Democrat Abhijit “Beej” Das, president and CEO of Troca Hotels, announced his bid this week. Like L'Italien, Mazen and until recently Koh, he also doesn't live in the district.

Democrat Lori Trahan, Meehan's former chief of staff, perhaps has the strongest Lowell bona-fides, having grown up in the city. She lives in Weston.

Rick Green, the only Republican actively campaigning for the seat, lives in Pepperell. And Louis Marino, who had filed to run as a Republican but switched his party affiliation to Democrat this week, is from Fitchburg.

Political diversions 

Dick Howe, a longtime observer of Lowell politics, said he still expects the city to play a role in determining the outcome of next year's election. Lowell still is technically the geographic center of the district, he noted, and the largest community in terms of population.

Howe said the city's political class have been preoccupied with city council races, with the preliminary round of voting this past Tuesday, and a divisive battle over where the city's new high school will be built, which has spilled over into the municipal elections.

"That's really sucking up all the oxygen in Lowell politics right now," he said. "And voters aren't focused on congressional politics yet."

If state Sen. Eileen Donoghue, a Lowell Democrat, jumps into the race, she could clear the field of Democratic contenders, he said.

Donoghue, who placed second behind Tsongas in the 2007 Democratic primary, is popular and would bring a large bloc of voters to the table.

Democrat Rodney Elliot, a former Lowell mayor and longtime city councilor, is also rumored to be considering a bid.

Howe and others say the loss of Tewksbury and Billerica, both considered part of the greater Lowell region, to redistricting in 2012 has diluted the city's influence in the district.

"It's a much bigger congressional district than it used to be, so I think the influence of Lowell has gone down," said Meehan, who represented the Merrimack Valley in Congress from the 3rd and 5th districts for 14 years.

Meehan, now president of the University of Massachusetts system, said the race to replace Tsongas will be "very expensive."

Raising enough cash to get out a message before next year's election, he said, will be more important to a candidate than what community they're using as a base.

"Geography means something in a congressional race, but it's not everything," he said. "The ability to raise money will be key to winning."

A changing district

David Torrisi, a former state representative and Meehan aide from North Andover, said the district's political center seems to be shifting away from Lowell.

"Years ago, being the only candidate out of Lowell was huge, but I don't think that's the case anymore," he said. "The district has really changed."

Haverhill is now the third-largest community in the district, with about 63,000 people, which would strongly benefit Fiorentini if he runs, Torrisi said.

L'Italien, meanwhile, has a base of support that could help her carry Lawrence, the district's second most-populous community with 80,000 people.

And Green could draw a lot of support from Winchendon and other red-tilting towns that went for Republican Donald Trump won in the 2016 presidential election.

Torrisi said Lowell still looms large over the election, but at this point it's a wide-open race.

“A strong candidate coming out of Lowell will be tough to beat," he said. "But if there's eight or 10 candidates in the race, all bets are off."

Christian M. Wade covers the Massachusetts Statehouse for North of Boston Media Group’s newspapers and websites. Email him at cwade@cnhi.com

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