(CNN) -- — Frustrated Republicans are retaliating for a Democratic power play to weaken their hand in opposing presidential nominations by forcing an all-night session.
Votes on judicial and other appointments were set in the early morning hours on Thursday as fallout over efforts by majority Democrats to enforce their rule change to expedite consideration of appointments, the so-called "nuclear option," grew more intense.
"The Obama administration and its allies have done just about everything to get what they want, one way or the other -- even fundamentally altering the contours of our democracy when they couldn't get their way playing by the rules," Senate Minority Leader Mitch McConnell said in floor remarks on Wednesday. "We saw the culmination of that with the Majority Leader's power grab in the Senate last month."
Republicans are requiring the marathon session if Democrats want to clear a long list of nominees before leaving for their holiday vacation next week.
GOP escalation of the rules fight renewed attention to sharp partisan wrangling one day after lawmakers trumpeted a compromise House-Senate budget proposal brokered across party lines.
Until last month, longstanding Senate rules required a supermajority of 60 votes to break a filibuster over a presidential nominee. Republicans fiercely opposed the change, which now allows the majority Democrats to break filibusters with 51 votes.
Democrats, who hold a 55-45 advantage in the Senate, said Republicans had abused the filibuster privilege around President Barack Obama's nominations, and the only way for him to promptly staff his second-term administration and move stalled judicial appointments was to speed things up through a rules change.
The first vote in the extended session is planned for 1 a.m. ET to confirm Nina Pillard to serve on the federal appeals court in Washington, for some a stepping stone to the Supreme Court.
Another vote could come about 5:30 a.m. ET to break a filibuster of Chai Rachel Feldblum to be a member of the Equal Employment Opportunity Commission.
Senate Democrats began enforcing the "nuclear option" earlier this week, stoking Republican ire.
Democratic Senators made plans to preside in the chamber overnight but aides said it was unlikely many others would be on hand except for votes.
All-nighters could continue for days. Democratic leaders said they were prepared to stay in session virtually around the clock through Saturday night to confirm a list of 10 nominees to a variety of senior posts.
They range from lesser known appointments -- such as Patricia Wald to be a member of the Privacy and Civil Liberties Oversight Board -- to critical positions-- such as Jeh Johnson to be Secretary of Homeland Security.
There are also several federal district court judges on the list as well as nominees to Pentagon posts and the State Department.
Customarily, Senate leaders work together so the chamber can conduct its business during more regular hours. But because of strict parliamentary rules, it's easy for just one Senator to hold things up.
In this case, the whole GOP conference is upset.
So why are they working overnight?
According to Senate rules, a certain number of hours of debate can still be demanded by any Senator once a filibuster is broken.
Known as "post-cloture debate time" in Senate parlance, up to eight hours of debate time is allowed for nine of the 10 nominees on Majority Leader Harry Reid's list. For the Johnson, the debate can last for 30 hours.
Typically, Senate leaders would agree to allow that debate time to run with the Senate out of session. But because Republicans are angry about the changes to the filibuster rules, they are requiring the Senate to stay in session.
Reid accused Republicans of obstructionism.
"It is hard to imagine a more pointless exercise than spending an entire day waiting for a vote whose outcome we already know," Reid said about the Pillard nomination. "But Republicans insist on wasting time simply for the sake of wasting time. It's no wonder Americans overwhelmingly support the changes Democrats made to the rules last month in order to make the Senate work again."