Sen. Bernie Sanders (I-Vt.) placed a hold on Wednesday night on Federal Reserve Chairman Ben Bernanke's nomination to a second term in that position.

Sanders, who had said he would oppose a second term for Bernanke, invoked the Senate practice, effectively blocking Bernanke's nomination from moving forward for the time being.

"The American people want a new direction on Wall Street and at the Fed. They do not want as chairman someone who has been part of the problem and who has been responsible for many of the enormous difficulties that we are now experiencing,” Sanders said in a statement. “It’s time for a change at the Fed.”

Lamakers on the left and the right have been reluctant to throatily back a second term for Bernanke. And while a second term for the Fed chairman is still seen as likely, Sen. Bob Corker (R-Tenn.) said on Tuesday he's unsure whether Bernanke has the votes, while Sen. Sheldon Whitehouse (D-R.I.) excoriated the Fed chairman in an interview with the Huffington Post.

Bernanke will face questions on his nomination to a second term on Thursday before the Senate Banking Committee. Sanders does not sit on that committee.

Bernanke was first appointed Fed chairman by President George W. Bush. He was nominated to a second term by President Barack Obama in August after having been widely credited for engineering the bailouts for the financial industry.