A liberal group founded by former Vermont Gov. Howard Dean (D) is wading into some of Virginia’s most notable House of Delegates races, pledging money and support for Democratic challengers.

Democracy for America announced Thursday that it is endorsing Kathleen Murphy (D) in her effort to unseat Del. Barbara Comstock (R) from the 34th district, which includes parts of Fairfax and Loudoun County. Murphy is the third Northern Virginia Democrat to receive the group’s backing, along with Jennifer Boysko, the challenger to Del. Tom Rust (R-Fairfax) , and John Bell, the opponent of Del. David Ramadan (R-Loudoun).

The group also released the results of surveys from Public Policy Polling, a firm that uses automated dialing rather than live telephone interviews, showing that many residents of the three Northern Virginia districts have negative views of the tea party movement and of Attorney General Ken Cuccinelli II, the Republican nominee for governor.

The endorsements are part of DFA’s Purple to Blue project, which seeks to win swing legislative seats in states around the country. The group says it will target two more districts in Virginia and will “spend well over $750,000” on the five Virginia races.

In an interview, Ramadan said he was unconcerned by DFA’s intervention in his contest.

“It doesn’t make any difference except that this will be out-of-state money for my opponent,” Ramadan said. “We’re ready for it. . . . I’m looking forward to re-winning my seat decisively.”

Susan Falconer, Comstock’s campaign manager, said “it is not surprising that [Murphy] would seek out and align herself with the extremely divisive, screaming. and ranting Howard Dean who was even soundly rejected by 93% of Virginia’s Democrats when he ran for President and knows nothing of Northern Virginia priorities.”