With the number of judicial filibusters growing by the week, Senate Republicans are preparing for a major floor action in the fall highlighting their allegations of unprecedented Democratic obstructionism.

Republicans are heading toward a choice between stacking up a one-day record number of cloture votes on controversial nominees or pulling the trigger on the so-called “nuclear” option, unilaterally changing the cloture rules on a simple majority vote, according to numerous GOP Senators and aides.

Republicans have ruled out launching the kind of 40-hour marathon debate they did last fall, but they have decided that they need to make another statement to further demonstrate the Democratic judicial blockade and energize base voters alienated of late on the GOP’s inability to break through on the nomination front.

“Before we break, before the election, you’ll see a very high-profile effort,” said Sen. John Cornyn (R-Texas), a member of the Judiciary Committee.

The line in the sand over nominations was drawn again Tuesday when Democrats officially blocked cloture on another circuit court nominee, William Myers, launching their seventh judicial filibuster of the 108th Congress, easily a record for the most judges rejected by cloture in one Congress.

And several more nominees considered controversial by Democrats are waiting in the wings, including three Michigan nominees to the 6th U.S. Circuit Court of Appeals who have cleared Judiciary and are awaiting floor action.

Judiciary Chairman Orrin Hatch (R-Utah) predicted Tuesday that the number of Democratic filibusters would hit double digits before the Senate adjourns in the fall. “There will be 10, maybe more,” he said.

Republicans now have to decide how to play out their judicial endgame, whether they can gather enough votes in their Conference to win a “nuclear” vote on the floor or if they just pursue a series of cloture votes all on one day to get as much attention to the topic as possible.

Sen. Trent Lott (R-Miss.) is leading the effort to gather support for the nuclear option, which would involve a request for a ruling from the chair that filibusters of judicial nominees were unconstitutional. The chair would likely be occupied by either Vice President Cheney or Sen. Ted Stevens (R-Alaska), the chamber’s President Pro Tem.

After the ruling came down against filibusters, Democrats would object and demand a vote, requiring Republicans to round up 50 votes on their side to do away with filibuster on judges. Because it is such a rarely used parliamentary maneuver, Democrats have vowed to bring the chamber to a near-complete halt if the GOP takes the step and is successful.

“It would be a disaster for them,” Minority Leader Tom Daschle (D-S.D.) said Tuesday.

Senate Republicans have long admitted, however, that they simply don’t have the votes from their own ranks to go the nuclear route, knowing that conservative Sen. Zell Miller (D-Ga.) is the only vote they will get from the minority.

But Lott said Tuesday that he has been working his colleagues on the issue and that he sees a chance for getting to 50 votes by the fall. “We’re about there, and I hope to have it before we go home,” he said.

“We are closer than we have been in the past,” Cornyn said.

Lott’s efforts to secure votes for the extreme option are separate from his task of examining changes in the internal Senate Republican Conference rules. He’s leading the charge, aides said, partly because of his new role as Rules chairman and partly because his past tenure as GOP leader left him with many relationships with Senators that he can employ in the process.

But this task may be a bit too much even for Lott, given the stiff resistance to the nuclear route from GOP moderates as well as some “old bull” committee chairmen.

Two Republicans reiterated their opposition Tuesday to the unilateral change in chamber rules on judicial filibusters.

“I’m very nervous about it, but I’m willing to listen,” said Sen. John McCain (R-Ariz.), chairman of the Commerce, Science and Transportation Committee.

“I’m very reluctant,” said Sen. Lincoln Chafee (R-R.I.). Asked if he could envision any scenario in which he’d support such a move, he said, “I don’t see that … but I’m always willing to listen.”

Some aides suggested that the Old Bulls had grown so increasingly frustrated with Democrats and Daschle’s objections to moving bills to a House-Senate conference, that more of them were willing to support the option than ever before.

It’s unclear whether Majority Leader Bill Frist (R-Tenn.) would hold the vote on the nuclear option if he knew he didn’t have the votes, whether there was a way to lose the vote but still win politically.

If they don’t push the judicial nuclear button, Republicans expect at minimum to have a day-long voting session of cloture votes on the controversial judges still awaiting floor votes. A deal in the spring allowed for up-or-down votes on 25 noncontroversial nominees, each of which has since been confirmed, in exchange for Frist’s promise to hold off on any controversial votes and a vow from President Bush not to make any further recess appointments of judges this year.

With that deal settled, conservative activists are urging Frist to bring as many controversial nominees to the floor as possible, guessing that by year’s end Democrats could have to filibuster as many 16 nominees for the entire 108th Congress.