Rep. John Tierney (D) raised less than his Republican challenger in the third quarter, Roll Call has learned.

Tierney raised more than $500,000 from July 1 to Sept. 30, while former state Sen. Richard Tisei (R) raised more than $660,000. Tierney, locked in a fierce battle with Tisei for Massachusetts’ 6th district, which is anchored in the North Shore region of the state, has now been outraised by Tisei for four consecutive quarters.

Though the 6th district is reliably Democratic, either candidate could win the race. Tierney has taken a political body blow from the innuendo surrounding his wife’s family’s legal troubles connected to an offshore gambling operation, although he has been accused of no wrongdoing

Tierney, an attorney and member of the Oversight and Government Reform Committee, ranks on Roll Call’s list of the 10 most politically vulnerable Members of Congress.

Roll Call rates the 6th district race as a Tossup.