Updated 11:59 a.m. | The Senate GOP minority may have found its greatest weapon in responding to a “nuclear” rules change: the clock.

The Senate stayed in session from Wednesday afternoon into the early morning Thursday to burn through hours and hours of post-cloture debate time on a number of President Barack Obama’s nominees to executive and judicial posts. The long hours, which could continue into Saturday, is the first real test of attrition for Democrats in the aftermath of last month’s rules change.

It’s the expense of time, more than anything said on the floor, that could make life difficult. When the process is completed, as many as 11 of the president’s choices will be confirmed to their new jobs.

Majority Leader Harry Reid, D-Nev., said that this might not be the only list of names to be processed before the end of the year because, as it turns out, Christmas isn’t the only deadline confronting the Obama nominees. A provision of Senate rules requires pending nominations to be sent back to the White House at the end of the session, unless there’s unanimous consent to hang onto them.

“If we have to work Monday before Christmas, we’re going to do that. If we have to work through Christmas, we’re going to do that, because I know the game they’re playing,” Reid said of the chamber’s Republicans. “They have done it before. A lot of these nominations will have to be sent — not have to be, but they will ask that they be sent back to the administration and we’ll have to start all over on those again, but some of them we’re not going to start all over again.”

Reid was alluding to Senate Rule XXXI, which states in part: “Nominations neither confirmed nor rejected during the session at which they are made shall not be acted upon at any succeeding session without being again made to the Senate by the President.”

What took place starting Wednesday afternoon — and could possibly extend into the weekend — emanated from the fact that the 56 “yes” votes constituted success for Reid in the first place. That wasn’t the case until the Nevada Democrat led his caucus in effectively changing the rules with a simple majority by using the “nuclear option” to set a precedent for limiting debate on almost all nominations without 60 votes.

“I’m very concerned … that we have put the United States Senate in a position where it is a very, very vulnerable body,” said Sen. Mike Johanns, R-Neb. “When the majority decided that it would bypass the requirement that rules would be changed by a two-thirds vote and do it by appealing the ruling of the chair, they put the United States Senate in a position where there are no rules. There are no rules.”

Democrats note more than a dozen relatively recent instances of using rulings from the chair to change precedents without the two-thirds needed to invoke cloture on rules changes, though none of them were as sweeping as what took place on Nov. 21. In surveying the new landscape, it was clear that the level of GOP retaliation would become a key story in December, but it wasn’t at all clear in what way. When Reid moved Monday evening to invoke cloture on 10 nominations, a counterattack was inevitable.

Sen. Lamar Alexander provided a telling a quote, responding to Reid that evening: “Until I understand better how a United States senator is supposed to operate in a Senate without rules, I object.”

Georgetown law professor Nina Pillard was the first to win confirmation as part of the marathon, with senators voting 51-44 in her favor around 1 a.m. Thursday. Three Democrats were among the senators voting “no.”

After a successful vote to limit debate on the nomination of Chai Feldblum to the Equal Employment Opportunity Commission, the next vote was set for 9 a.m. on her confirmation.

While the most-often cited reason for opposing Pillard’s nomination to the D.C. Circuit Court of Appeals stems from a contention that the seat shouldn’t even exist, Minority Leader Mitch McConnell of Kentucky was among the Republicans criticizing Pillard on the merits during the debate.

“A review of her legal views makes one thing clear: the nominee before us is a liberal ideologue — in other words, just the kind of person this administration was looking for to rubber stamp its most radical legislative and regulatory proposals on the D.C. Circuit Court,” McConnell said.

Democrats, of course, cite Pillard’s legal background in saying she is eminently well-qualified for the bench. As for the other judicial nominations in the queue, McConnell blasted Reid for opting “to spend the week on nominations that are not emergencies.”

Sen. Max Baucus, D-Mont., contradicted that argument early in the floor debate, highlighting two nominees for federal district judgeships in Montana on the list for confirmation are to fill judicial emergency vacancies.

“Chief Judge Dana Christensen, our lone active judge, travels over 300 miles round trip to hear cases,” Baucus explained.

Counting the Pillard nomination, which Democrats broke a filibuster on not long before Reid filed Monday’s motions, nine of the 11 nominations in the queue get debate times of four hours or less, with some only getting an hour if Democrats abstain from using their time. Obama’s choice of Jeh Johnson to head the Department of Homeland Security is the last in the sequence. If Republicans use all their time, a Senate Democratic aide suggested the Johnson confirmation vote would come up on Saturday afternoon.

Republicans weren’t the only ones to speak on the Senate floor as the time burned.

Just as he does every week the Senate is in session, Rhode Island Democrat Sheldon Whitehouse delivered a speech about energy and climate issues, accompanied by a chart with the slogan “Time to Wake Up.” On Wednesday, a staffer brought that chart to the Capitol more than four hours before Whitehouse was able to make his presentation.

Update 11:59 a.m.

The Senate confirmed the Feldblum nomination 54-41, as well as the nomination of Elizabeth A. Wolford to be a federal district judge in New York, with the pattern of votes continuing for the foreseeable future.

In another development, Republicans once again invoked the two-hour rule, declining consent for the Judiciary and Foreign Relations committees to conduct business during the ongoing voting.