ABC's Z. Byron Wolf reports: Senators unanimously added an amendment to their Wall Street reform bill to audit emergency spending at the Federal Reserve. The language is watered down from what Sen. Bernie Sanders, I-VT, originally wanted — a full and ongoing audit of the Fed. But in its new version, containing the audit, which will be performed by the Government Accountability Office, only to emergency spending, the amendment passed 96-0. A vote on Sanders original amendment, offered by Sen. David Vitter, R-La, failed 37-63. That original audit proposal passed the House with bipartisan support in 2009. American taxpayers do not know the full extent of emergency spending or who benefited from measures the Federal Reserve has employed to prop up the US economy since 2007. Fed Chairman Ben Bernanke and the Obama administration have argued that opacity is necessary for the Fed to function properly and independent of day-to-day meddling from Washington. The votes Tuesday were delayed from last week in part so that Sen. Bob Bennett, R-Utah, could take part. Bennett had been fighting for his political life in Utah, but he was excluded Saturday from the Republican primary to be reelected to his Senate seat. He was excluded by supporters for candidates more friendly to Tea Party activists. Auditing the Federal Reserve, or even ending it, is a major issue for much of the grassroots Tea Party movement. Tea Party godfather Ron Paul published a book titled “End the Fed” in 2009. Bennett was one of four Senators to miss the vote Tuesday.