Senate Majority Leader Harry Reid (D-Nev.) has turned to Judiciary ranking member Arlen Specter (R-Pa.) for help in shepherding conservative Republicans into a deal with GOP moderates and Democrats on comprehensive immigration reform before electoral politics kills the issue for the next two years.

A bipartisan group of about 10 Senators has been huddling behind closed doors with key White House officials for hours at a time to try to meet Reid’s timeline, on which the Majority Leader says he is inflexible. The group met for about three hours on Thursday and will resume talks this week.

But with progress still slow, Reid late last week said he would use a procedural maneuver known as “Rule 14” to push an immigration bill to the floor by May 14.

According to an aide to Reid, the Majority Leader is expected to bring up the bipartisan reform package passed by the Judiciary Committee last year under the stewardship of then-Chairman Specter, although if negotiations produce a deal he will allow lawmakers to propose it as a substitute amendment to the bill.

Reid “is prepared to give those negotiating a compromise plenty of time,” the aide said, adding that bringing last year’s bill to the floor “doesn’t mean negotiators can’t keep working on a deal to offer as a substitute amendment.”

Reid has turned to Specter in the hopes of turning up the heat on Republicans to get a consensus measure ready for floor consideration. Specter, a moderate, was a leading negotiator on the previous Congress’ bipartisan measure, which cleared the Senate but ultimately died in conference committee.

Specter seems mildly more optimistic than some of his colleagues about the chances of Reid’s timeline being met, saying last week that there is “a prodigious amount of work that’s going on.” And while the different parties may appear to still be at odds, Specter said the Senate has shown that with any complicated legislative undertaking, “people argue until the last minute” and then come up with a deal.

Still, Specter did not dismiss the suggestion that the stakes are high: “If we don’t take advantage of this window of opportunity, the speculation is that there will not be another. We all realize the time is now.”

Senate Majority Whip Dick Durbin (D-Ill.) agreed that this likely will be the last chance to finish the bill and that any further delays will only erode what momentum negotiators have built up.

“Let’s talk about herd psychology here. If members of the Senate believe it’s coming, they will force themselves to compromise and make concessions and move toward a bill. And if they believe they might put it off … everybody will go fishing,” Durbin said.

Additionally, Durbin noted that procedurally, there will be few chances to return to immigration following the Memorial Day recess given Democrats’ push to complete all of the fiscal 2008 spending bills by October.

“It’s really hard to return to. It is a two-week commitment and we just don’t have that kind of time. We’ve got all the appropriations bills to deal with and we’re really focusing — House and Senate — on the impossible dream [to] finish the bills on time,” Durbin said.

“We’ve got to get a bill drafted and consequently agreed to by the 14th,” said Sen. Mel Martinez (R-Fla.). “Otherwise, the issue will be dead for this Congress, and probably the next two or three years.”

Following Thursday’s closed-door session on the issue, Senators were reserved in their optimism, but there was near unanimity about the consequences of their failure. Those lawmakers acknowledged they have about a week to work through the delicate pieces of a measure that has bedeviled the chamber for about three years.

“We are racing against the clock,” said Sen. Bob Menendez (D-N.J.) as he exited the Thursday session. “I am a jogger, but not a marathoner. Right now we need sprinters.”

Menendez added that while progress is being made, the group is “not anywhere near a deal.”

But despite this sense of urgency on the part of a number of lawmakers, several, including Sen. John Cornyn (R-Texas), have cautioned against rushing to a floor debate.

Cornyn, arguably the most conservative Senator in the negotiations, said he doesn’t view this month as the final chance to produce a consensus package, acknowledging it is a “complicated bill” that requires a heavy lift on all sides.

“I don’t think it’s critical we get it done before [the end of] May, but it’s probably critical we react to an August deadline,” Cornyn said.

Similarly, Sen. Jeff Sessions (R-Ala.) on Friday criticized Reid’s decision to begin the process of bringing legislation to the floor and argued Democrats should give the bipartisan negotiating process time to work.

“Sen. Reid is squandering a historic opportunity for bipartisan support for comprehensive immigration reform that will actually work,” Sessions said. “He appears to be allowing the wishes of the special interests that forced last year’s legislation to chart the course again this year. In my view, that is simply unthinkable. The Democratic leadership acts like this is just another piece of everyday legislation, but it is not. The immigration bill is one of the most important to come through the Senate in the decade that I have been here.”

Sen. Jon Kyl (R-Ariz.), another conservative who is viewed as the linchpin to solidifying a bipartisan deal, said last week that chances were 50-50 that an agreement would come together. But Kyl acknowledged the clock is ticking.

“It’s really hard,” Kyl said. “I do think there’s a desire on the part of Republicans and Democrats to get a consensus bill. But time is very short, emotions are very high and the deadline is very tight.”

Kyl, the Republican Conference chairman, finds himself in a difficult position this year on the immigration debate. He has come under increasing fire from conservative bloggers and other commentators for being too closely aligned on the issue with President Bush, who conservatives complain is taking a far too liberal position, while Democrats recently have begun to paint Kyl as an obstruction to reaching a deal.

For instance, when asked whether negotiators can come to a deal that Kyl and other conservatives can agree to, Durbin argued that many of his positions are too far to the right for most lawmakers.

“I’m glad Sen. Kyl is at the table, but … he is now a convert to the cause,” Durbin said. “He was very strident in his opposition [to] immigration [last year]. We’re glad to have him, but some of his ideas will be difficult for the majority to accept. So if we are supposed to wait until his ideas become part of the bill, it may never happen.”

But a GOP aide familiar with the issue rejected Democratic complaints, arguing that Kyl is working in good faith and that Democrats are attempting to deflect liberal criticism of the bill on to the GOP.

“They are dealing with very hostile far-left groups that are creating trouble,” the staffer noted. The aide also said that such complaints appear to be a way for Democratic leaders to frame their decision to use Rule 14 as their last option in the face of conservative opposition.

“You have a situation where they may bring a bill to the floor that is not a compromise [but] they’re trying to frame it” in such a way as to avoid criticism, the aide maintained.