(Reuters) - Judy Shelton, Republican President Donald Trump’s contentious pick to fill a vacant seat at the Federal Reserve, faced a more difficult road to confirmation as the U.S. Senate adjourned on Wednesday until after Thanksgiving. On Tuesday, the Republican-controlled Senate failed to muster the required votes to move her nomination ahead in the confirmation process. That was in part because a couple of Republicans joined Democrats in opposing Trump’s former economic adviser out of concern her perceived partisanship could imperil the Fed’s independence. In addition, two other Republicans had to skip the vote because they were quarantining due to the coronavirus. Shelton has come under fire for inconsistent, controversial views, including an embrace of the gold standard and a shifting stance on interest rates as control of the White House passed from Democrat Barack Obama to Trump. When the Senate comes back in session, on Nov. 30, Republican Senate Majority Leader Mitch McConnell could call another vote. But it is not clear when the two senators who are currently quarantining - and whose votes McConnell needs to move Shelton’s nomination forward - can return to the Senate floor. One of them, 87-year-old Chuck Grassley, tested positive on Tuesday. On Wednesday, he tweeted that he was symptom-free. The number of ‘no’s are also set to increase. Republican Senator Lamar Alexander, who was not in Washington for the vote this week, opposes Shelton’s nomination. Newly elected Democratic Senator Mark Kelly is eligible to take the oath of office as soon as Arizona certifies its election results, which is scheduled for Nov. 30. He expects to take office in early December. McConnell, in wrapping up on Wednesday, did not say anything about Shelton.