The Minnesota Democrat's swearing-in marked the end of an eight-month political and legal struggle and drew thunderous applause and a standing ovation in the Senate chamber. His presence gives Democrats 60 votes, enough to thwart possible Republican filibusters.

Vice President Joe Biden administered Franken's oath, slapping the former "Saturday Night Live" performer on the back, then hugging him. Former Vice President Walter F. Mondale, a Minnesota native, accompanied Franken. Franken was introduced by his fellow Minnesota Democratic senator, Amy Klobuchar.

Franken arrives in the Senate more than eight months after Election Day. Last week the Minnesota Supreme Court unanimously ruled in Franken's favor after a protracted recount and his opponent, former Republican Sen. Norm Coleman, conceded.

In the usually staid Senate, there were plenty of signs that something unusual was afoot. The Senate Gallery, rarely full even with dozens of summer tours, was packed with onlookers. After Franken took the oath of the Senate, the gallery erupted in an unusual and lengthy applause that continued for several minutes.

The hullabaloo that accompanied his swearing in was in some ways a contrast with the image Franken is trying to project as a serious-minded senator.

Since moving back to Minnesota in 2005, Franken has tried to tone down his image as an irreverent satirist, casting himself as workhorse and policy wonk. *