Updated 11:40 p.m. | An independent candidate is seriously weighing a run against vulnerable Massachusetts Rep. John Tierney (D), Roll Call has learned.

Sources were unwilling to name the candidate on the record, but described him as a retired Marine in his early 30s who grew up in the district. The potential candidate, who would plan to caucus with Democrats if elected, is not registered with either party and has never been involved in elective politics. The potential candidate, who has not made a final decision on a Congressional bid, thinks he could raise a million dollars before November.

“Let’s face it, it’s a volatile year that you don’t see very often and it’s worth this candidate taking a look at this race,” said a source who has been briefed on the potential candidate’s deliberations.

Tierney, who has had a rough few weeks, already faces a strong challenge in the Bay State’s 6th district from Republican Richard Tisei, a former state Senator.

The eight-term Congressman faced allegations that he had knowledge of his in-laws’ gambling operation and held a press conference last week in an attempt to answer questions and turn the page away from a politically damaging story. But his vulnerability has stirred the interest of at least one ambitious potential politico.

The potential candidate would have a compressed time frame should he decide to pull the trigger on a Congressional bid. Petitions for non-party candidates are due to local election officials for certification by July 31. Two thousand signatures are required to get on the November ballot without a party affiliation. To run as a non-party candidate in Massachusetts one must be un-enrolled in one’s current voter registration.

Roll Call currently rates the race as Leans Democratic.

Updated

The candidate considering a bid in the 6th district is 33-year-old Seth Moulton. The Marblehead, Mass., native is a graduate of Phillips Academy and a triple-degree holder from Harvard University. He served four tours as a Marine in Iraq and currently works for a railroad company in Texas.