As the Senate Republican leadership quietly gauges GOP support for a constitutional amendment to ban same-sex marriage, some Democrats are considering the merits of allowing a direct vote on the issue, rather than trying to derail the GOP effort by a procedural move.

Leaders in each party are gaming out strategy in anticipation of next week’s battle over gay marriage — a showdown prompted by Republicans’ desire for a wedge issue they can use with undecided voters in November.

The GOP leadership is currently engaged in its whip count, and Senate Majority Leader Bill Frist (R-Tenn.) said he doesn’t expect to have an accurate assessment until the “early part of next week” when the chamber turns its attention to the issue. Frist did add that the leadership’s efforts would ultimately focus on “10 people who could swing” their vote either way on the issue.

The GOP leadership is expected to exert intense pressure on each of the 51 Republican Senators — even those who would ultimately oppose the amendment — to help overcome a procedural hurdle that Democrats may use to prevent a vote.

In order to achieve cloture and thus allow the Senate to vote on the bill, Republicans would need 60 votes — a threshold that they are considered unlikely to reach. The bar for approving a constitutional amendment is even higher, with 67 votes needed for the Senate to give its final stamp of approval to a constitutional amendment.

“Everybody understands this is all hands on deck,” said Sen. Trent Lott (R-Miss.). “Everybody should vote for cloture even though you may not support that at the end.”

The Republican leadership has scheduled a special meeting with rank-and-file Members this morning to discuss strategy for the upcoming debate. A GOP leadership aide said that Republican leaders are mulling whether to use the original language drafted by Sen. Wayne Allard (R-Colo.), which bans same-sex marriages, or another version that would simply define marriage as a union between a man and a woman.

However, Democrats may let the GOP leadership off the hook. Democratic leaders are considering whether to let the GOP have a direct vote on the constitutional amendment.

While the Democrats are still considered likelier to force a cloture vote that the GOP is expected to lose, some Democrats believe that an up-or-down vote on the issue would be more beneficial, according to three separate sources, all who requested anonymity.

“Having a vote on the issue would put it to rest,” said one of the sources, a senior Democratic aide.

Democrats who advocate this course said forcing a procedural vote would provide an inaccurate sense of support for the measure. Many GOP Senators who would be tempted to vote against the amendment itself, they say, might support the Republican leadership’s right to proceed to the bill, which would become the only vote of record on the issue this year.

By contrast, allowing a direct vote on same-sex marriage would prevent Republicans from characterizing Democrats as obstructionists — and would force some GOP Senators to take a difficult vote on the issue.

“It would put their hypocrisy on the record,” said a Democratic source. “There are many Republican Senators who are embarrassed by the bill and would prefer not to vote to amend the Constitution.”

Todd Webster, a spokesman for Senate Minority Leader Tom Daschle (D-S.D.), downplayed speculation about the Democratic strategy.

“There is no decision on how to proceed, as the votes simply aren’t there,” Webster said. “There are 55 to 60 votes against amending the Constitution, which demonstrates how nakedly political this effort is. Americans are eager to find out whether the Washington Republicans put as much effort into lowering drug prices, expanding access to health care or raising the minimum wage.”

Sen. Dick Durbin (D-Ill.) said he expects Democrats to choose to block the measure through procedural means, which would let the Senate shift its focus to more pressing legislative issues.

“We are going to have a motion to proceed, and I think we will prevail, and that will be the end of it,” he said.

Durbin decried the Republican leadership’s attempt to raise the issue, saying it was a partisan exercise concocted to appease the GOP’s base of socially conservative voters.

“This is not a serious effort to amend the Constitution — this is a serious effort to create an issue for November,” Durbin said. “They want a roll-call vote, and they want to put Senators on the spot. And I frankly don’t think we are going to step back and let that happen.”

But Senate Republican Conference Chairman Rick Santorum (Pa.) dismissed Democratic criticism, saying any vote on the issue will be an accurate measure of a lawmakers commitment to the sanctity of marriage.

“The fact that we are having this vote is the most important thing,” he said. “You can call it a procedural vote, but it is a vote as to whether you believe that marriage should be protected. You can spin it anyway you want [but] the bottom line is if we do not do something to protect marriage, marriage as we know it will be changed, potentially forever, and the consequences on our society will be dire.”

It is unclear whether Sen. John Kerry (Mass.) or Sen. John Edwards (N.C.) — the presumptive Democratic presidential and vice presidential nominees — would leave the campaign trail next week for a vote on the issue. Privately, Republicans acknowledge they are eager to get both men on the record opposing the constitutional amendment banning same-sex marriage, because they believe such a vote would hurt them in the South and Midwest.