WASHINGTON — Maine’s Democratic congressmen ranked among the most liberal in an index that rated lawmakers by how they voted on key issues.

The Aug. 16 issue of The New American, a biweekly conservative magazine, graded all 535 congressional delegates based on votes they cast on a variety of issues, including the impeachment of President Clinton, gun control, the war in Kosovo, funding for the Peace Corps, deployment of a national missile defense and flag desecration.

Rep. John Baldacci of Bangor scored 15 out of 100, and Rep. Tom Allen of Portland scored 17, with 100 being the most conservative. The magazine gave minuses to “incorrect” votes, or votes that they do not consider to represent conservative ideology, and pluses for “correct” votes. There were 40 issues total, 20 in the House and 20 in the Senate.

“A high score indicates that a congressman usually voted for constitutional principles of limited government; a low score indicates the reverse,” stated the magazine, which has a circulation of 50,000.

Baldacci, who got the same score as House Minority Leader Dick Gephardt, D-Missouri, said he didn’t mind being rated so low.

“I don’t have any problem being rated by anybody,” said Baldacci. “[I’m] a public servant and it’s my job to listen to people. We’re not always going to agree.”

Anyone can tailor a ranking to suit a specific agenda, said Mark Sullivan, a spokesman for Allen.

“You can find a lot of different organizations rating members with an agenda in mind,” Sullivan said. “And an organization that’s looking to label someone on these hot-button issues, that’s where [Allen’s] going to lie, because these are issues of principle.”

Rep. James McGovern, who represents Massachusetts, one of the most liberal delegations made up of all Democrats, had a score similar to Maine’s congressmen.

“Fortunately, I represent working families in Massachusetts, not rabidly partisan magazine editors. On each and every issue before Congress, I vote my conscience and vote with the best interests of my constituents in mind,” McGovern said. “If voting to fund the Peace Corps and to close gun loopholes makes me unpopular with the New American, that’s OK with me.”

Republican Sens. Olympia Snowe scored 55, and Susan Collins scored 60. They were given minuses for voting in support of a number of amendments to the Senate gun control bill passed in May, including an amendment that would ban assault weapon sales to minors, which was adopted 96-2.