Dec 19 (Reuters) - For judicial confirmations, 2011 went out not with a bang but a whimper.

The Senate didn't confirm any of the pending 21 judicial nominees before adjourning for its end-of-the-year break on Saturday. The lack of action further stalled the Obama administration's chances of making headway on a nominee backlog that is threatening to slow down the federal courts.

Currently, there are about 80 vacancies on the federal bench.

The Senate to date has confirmed 124 circuit and district court nominees during Obama's first three years in office; during the comparable period for Obama's predecessor George W. Bush, the Senate confirmed 168 nominees.

The chamber will often take up a slew of nominees before a long break. At the end of 2010, for example, the Senate confirmed 19 judicial nominees before it broke for its holiday recess. By contrast, this December the Senate has confirmed just five nominees. The last confirmation was that of Morgan Christen to the 9th Circuit Court of Appeals on December 15.

Judicial confirmations have been caught in partisan wrangling over recess appointments. Republicans have tried to hinder the administration from filling a vacancy at the helm of the new consumer watchdog agency by a recess appointment, a method that would avoid a protracted confirmation battle.

Republicans allowed few confirmations to go through after Senate minority leader Mitch McConnell said on Saturday he didn't receive word from the president that he would "respect practice and precedent on recess appointments."

The Senate is now in a "pro forma" session, meaning it meets briefly every few days, rather than in an actual recess. That prevents the President from making a recess appointment.

Absent unanimious consent from all senators - a highly unlikely scenario given the rancor in Washington these days - the chamber won't take up any nominations until it returns next month.

Also on Saturday, the Senate returned eight judicial nominees to the President, a formal process that requires the administration to re-nominate those nominees. Such nominees are often considered to be endangered; Caitlin Halligan, a federal appeals nominee who earlier this month was effectively filibustered by Senate Republicans, is one such nominee returned to the President. All other pending nominations will remain in effect.

The Senate is scheduled to take up its next judicial confirmation vote on January 23, when it considers the nomination of John Gerrard to be district court judge in Nebraska.

(Reporting by Carlyn Kolker)

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