Keller @ Large: Tierney Up For Fight Against Tisei In Congressional Election

BOSTON (CBS) - It's been 18 years since Massachusetts elected a Republican to the U.S. House, but that may change in November.

It looks like six-term incumbent John Tierney has a fight on his hands.

Former State Senator Richard Tisei is actually leading Tierney in a poll commissioned by his campaign.

The Tierney camp says their polling shows the incumbent well ahead, but dueling polls aside, an exchange over same-sex marriage illustrates how difficult it may be for Tierney to shake off his challenger this time around.

Tisei, a politically moderate former State Senator who also happens to be openly gay, could be Tierney's worst nightmare.

His support of same-sex marriage has helped win him the endorsement of the Gay and Lesbian Victory Fund, and the Pro-Gay-Marriage Log Cabin Republicans.

But, when the president issued his gay-marriage endorsement last week, Tierney (who wasn't available for an interview Tuesday) claimed Tisei would enable House Speaker John Boehner in a right-wing battle against marriage equality.

"Richard Tisei embraces the Republican agenda on Capitol Hill, and John Tierney has been a consistent fighter on behalf of the middle class, and that's what matters to the people of this district," said Tierney spokesperson Grant Herring. "Richard Tisei will be a fighter for the Tea Party, and the Republican agenda."

"I want to work with the leadership to help solve the problems the country has right now, but I'm not gonna be a rubber stamp. Our current Congressman (Tierney) votes 99% of the time with the party leadership," said Tisei.

Normally, the presence of an acceptably-moderate Republican wouldn't matter that much in a Massachusetts
Congressional race.

But, Tierney's image took a hit during his wife's recent legal problems, and redistricting made the terrain in the sixth district more friendly for Tisei.