House Majority Leader Tom DeLay (R-Texas) said Tuesday that the chamber would take up a constitutional amendment banning gay marriage next week, setting the stage for a politically sensitive vote six weeks before Election Day.

DeLay said the vote would be on an amendment defining marriage in the United States as being between one man and one woman. A similar effort in the Senate was defeated in July on a procedural vote, 48-50.

House Republicans openly admit that the measure is unlikely to garner the two-thirds support necessary for passage, but they believe that holding a vote is important in building momentum behind the issue.

“I doubt that it will pass, but this is part of a long-term strategy to protect marriage in this country,” DeLay said.

DeLay and other Republicans see banning gay marriage as a cause that will move forward in incremental steps before finally being implemented. They compare it to the ban on late-term abortion, which took about a decade to get passed.

In the short term, however, Republicans acknowledge that staging a floor vote on the matter puts them in a politically advantageous position and forces Democrats to make potentially uncomfortable choices.

Carl Forti, spokesman for the National Republican Congressional Committee, cited South Dakota Rep. Stephanie Herseth (D) as the type of conservative-state lawmaker who could have difficulty with the vote.

“This is going to put people like her in a little bit of a box,” Forti said.

Herseth has said she would support a constitutional amendment, though Republicans have accused her of being inconsistent on the issue.

John Barrow (D), who is challenging freshman Rep. Max Burns (R) in Georgia’s 12th district, recently sparked controversy in that race by declaring that he would support a federal gay marriage amendment. During the Democratic primary he said he would oppose such a measure.

Democrats believe House Republicans are making cynical use of the chamber floor for political purposes, and that the vote will be a waste of time given the preordained outcome and the amount of work that remains on the House’s agenda this session.

“It’s clearly pathetic, given all that’s left on their plate,” said a Democratic strategist, adding that the vote would allow Democratic incumbents and challengers from conservative areas to reaffirm their positions. “It’s giving most Democrats — and Republicans — a chance to vote with their districts and take the issue off the table.”