Still short of the votes needed to change Senate rules, Republicans said they are likely to hold off on a unilateral attempt to end the Democratic blockade of judicial nominations until next spring at the earliest.

While backers of the so-called “nuclear” option of changing rules for approving judicial nominees claim they are closer than ever to a majority, GOP leaders say there is not enough time left in the legislative calendar to take such a risky move. Majority Leader Bill Frist (R-Tenn.), in listing last week his priority items, the must-do issues before the target recess date of Oct. 8, mentioned neither any judicial nominees nor an attempt at changing the filibuster rules.

“Everything’s still on the table,” Frist said after the press briefing. “But with [20 days] left, we’re going to stay focused on the security of Americans.”

That means the most likely time to try to force a rules change intended to end judicial filibusters would be sometime next spring, possibly in June and just before a potential Supreme Court vacancy or two could arise, according to Senators, aides and strategists.

That time line runs counter to the wishes of Sen. Trent Lott (R-Miss.), who has been leading the whip count for the nuclear option, as well as Sens. Orrin Hatch (R-Utah) and Rick Santorum (R-Pa.), all of whom are pushing to make the move this fall. Santorum, the Republican Conference chairman, said that a fall vote would be the most even-handed approach to take on the issue, giving Democrats a chance to agree to end filibusters when there’s still a chance of Democratic nominee John Kerry (Mass.) winning the White House.

“We can say to the Democrats: We won’t know who’s going to be president, we’re on even footing,” Santorum said.

Hatch, the Judiciary chairman, declared that he and Lott had rounded up enough support from within their Conference that they were just two votes shy of the 50 needed to change the rules unilaterally, with four undecided Senators, mostly moderates.

“If we get two of them, we’ve got it,” he said.

Lott was a bit more circumspect in his whip count, saying that they were “very close” to gaining the 50 votes needed.

The procedure would involve Senate Republicans asking for a ruling from the chair, which would be occupied by Vice President Cheney or the Senate’s President Pro Tempore, Ted Stevens (R-Alaska), that judicial filibusters are unconstitutional. It would then take just 50 votes, with Cheney breaking the tie, to uphold the ruling and outlaw the Democratic practice of mounting filibusters against President Bush’s nominees.

In the 108th Congress, Democrats have launched a historically unprecedented number of filibusters of judicial nominees, having blocked 10 nominations so far through the procedural tactic. While they have been otherwise gracious to many of Bush’s nominees — confirming more than 200 district and circuit court judges already in his first term — the most controversial picks have been denied lifetime appointments through filibusters.

According to one estimate by conservatives, prior to the 108th Congress only 14 judicial nominees had ever faced a cloture vote in the history of the republic — a figure that Democrats may top in just two years if Frist and Hatch put a few more controversial circuit court nominees to a vote before adjourning sine die.

Democrats have promised their own “nuclear” response in the chamber if the GOP makes the rule change, a procedure which was last used in bipartisan fashion in 1975, to set the required number of votes to end cloture on legislative issues at 60 instead of 67.

Sen. Pat Leahy (D-Vt.), the ranking member on Judiciary, practically dared Republicans to try to vote on the nuclear option in the fall, predicting a low number of votes for the conservatives because of fears that Kerry might win and the GOP would lose its ability to filibuster Kerry’s nominees.

“A lot of the steam is going out of this because they’re afraid Kerry’s going to win,” he said.

Because of the sensitive nature of the move, GOP leaders are wary of bringing it up for a vote unless they are absolutely certain they can win, something they currently don’t believe they can do, according to Lott and other aides and strategists.

“We’ve counted the votes. We know where we are,” he said.

On the Democratic side, conservative Sen. Zell Miller (Ga.) is the only vote Lott can count on, and interviews with Senators last week indicated that at least a handful of moderates and “Old Bulls” are opposed, or at least reluctant, to make the unilateral move to end filibusters.

“I’m not in favor of that,” said Sen. Lincoln Chafee (R-R.I.). “We’ve got to learn to work together here. We can do that.”

Other moderate Republicans such as Maine Sens. Olympia Snowe and Susan Collins are also not supportive of the move, as are Armed Services Chairman John Warner (Va.) and Commerce, Science and Transportation Chairman John McCain (Ariz.).

“Put me down as undecided,” Warner said, noting his opposition to the filibusters but adding, “I’m not sure the rules change is in the best long-term interest.”

Assuming Frist doesn’t change his mind, Lott said a push for the ruling from the chair could come next spring, particularly if the GOP picks up some seats in the November elections and the idea has more support.

Aides say a late-spring push for the ruling would allow for any of Bush’s new Cabinet nominees to get approved in the winter as well as let the budget process and any major legislative initiatives get under way before the fallout of the nuclear option hits.