The line to replace Rep. Marty Meehan (D-Mass.) has not gotten any shorter since speculation began a few months ago that the 14-year veteran would leave Capitol Hill for a job in academia.

Meehan will vacate his Lowell-based 5th district seat no later than July 1 to become chancellor of the University of Massachusetts Lowell, his alma mater, with a special election to follow later this year.

His announcement last week that he was taking the job set off a scramble, as the Massachusetts delegation has been static for years. A special election was held in October 2001 after veteran Rep. Joe Moakley (D) died that May, making Rep. Stephen Lynch (D) the first new Member since Rep. Mike Capuano (D) won election in 1998.

The Democratic primary will be the main event in the race as the 5th district gave the Democratic presidential nominees 57 percent of the vote in 2000 and 2004.

The early conventional wisdom puts Niki Tsongas, a college administrator and wife of the late Sen. Paul Tsongas (D-Mass.), at the front of the pack. She is followed closely by Eileen Donoghue, the former mayor of Lowell and currently a member of its city council, and Middlesex County Sheriff James DiPaola.

Some insiders also believe that David O’Brien, a Democratic National Committeeman, could be in the top tier.

State Reps. Barry Finegold, Jamie Eldridge and Jim Miceli certainly do not want to be counted out, nor does political consultant Stephen Kerrigan.

Finegold, who said he has been “left at the altar” twice before by Meehan, thinks he has an edge given that he is the only serious candidate from the Greater Lawrence area. All the other frontrunners either share Lowell as their base or are from less-populated parts of the district, he said.

Finegold established a Congressional campaign committee in 2001 when Meehan contemplated a gubernatorial run in 2002 but pulled the plug when Meehan changed his mind. Finegold was ready to run for Congress again in 2004 when Meehan, and several other Bay State House Members, prepared to run in a special Senate election under the assumption that Sen. John Kerry (D-Mass.) would win the presidency.

Finegold, DiPaola and Tsongas have filed candidate papers with the Federal Election Commission.

Tsongas, who previously formed an exploratory committee, reportedly has $130,000 in her war chest already. EMILY’s List, the Democratic powerhouse that supports women candidates who support abortion rights and was the biggest political action committee in the previous cycle, is very interested in electing a woman to Meehan’s seat, as the Massachusetts Congressional delegation is all male.

So far, however, EMILY’s List is not favoring Tsongas over Donoghue or vice versa, according to the group’s spokeswoman, Ramona Oliver.

Voters know Tsongas’ name, which is a big advantage, but Donoghue’s Lowell base is considerable, as is DiPaola’s given that he serves the whole county.

Neither Tsongas nor DiPaola currently live in the district, though both reportedly are renting apartments in Lowell.

Republicans mulling bids include Lawrence Mayor Michael Sullivan, former state Rep. Donna Cuomo and Charles McCarthy, who lost to Meehan in 2002.

Candidates will have to buy airtime in the expensive Boston media market so fundraising will be essential.

“There’s so much pent-up ambition, I don’t think anyone is going to take their name out of the running prematurely,” said one Bay State insider who did not want to be named. “Everyone’s in it until money becomes an issue.”

As if running in the condensed time frame of a special election were not difficult enough, the contenders also do not know when the special election will be held.

Massachusetts law, which was changed in 2004, requires the governor to order a special election no sooner than 145 days after a Congressman resigns and no later than 160 days.

If Meehan formally tells Gov. Deval Patrick (D) that he intends to quit Congress in the next week or two, the primary could be held in July. But if he waits until his July 1 start date at the university, it could be as late as November or December.

A spokeswoman for Patrick said that until Meehan submits his resignation letter, the governor cannot set an election date.

Patrick has not indicated if he has a preference about when the special elections should be held.