The U.S. Senate on Thursday voted to confirm Alan Greenspan (searchfor a fifth and final term as chairman of the Federal Reserve (search), clearing him to serve at the U.S. central bank into 2006.

The Senate backed Greenspan's renomination by voice vote without opposition just days before his fourth term was set to expire.

The Senate vote also comes on the eve of what is widely expected to be the first interest rate increase by the Fed in four years.

Fed officials are expected to nudge overnight rates up from their current low of 1 percent -- a low last seen in 1958 -- when they meet June 29-30 as a first step in a protracted rate-rise cycle.

Greenspan, 78, took the helm of the central bank in 1987, when he was tapped to serve an unexpired term as a member of the Fed's board by then-President Ronald Reagan (search).

He was renominated once by former President George Bush (searchthe current president's father, and twice by former President Bill Clinton (search). The current President George W. Bush nominated him for a final stint leading the Fed a month ago.

Already the second-longest serving chairman in the central bank's 90-year history, Greenspan has ably navigated market crashes, financial crises and the often rough political waters of Washington.

Greenspan's overwhelming backing in the Senate -- a foregone deal after Democratic presidential hopeful Sen. John Kerry (searchmade his support clear -- is a testament to both his political and economic prowess.

He presided over the longest U.S. economic expansion and has received credit for keeping the two recessions on his watch short and shallow.

The new four-year term as chairman will allow Greenspan to continue to serve until his separate 14-year term as a Fed board member expires at the end of January 2006.

Under the law, Fed board members can only serve one full term, and the chairman must be chosen from their ranks.

Greenspan could, however, continue to serve past January 2006 if not replaced by that time.