Al Franken, a writer, comedian and former Saturday Night Live cast member, is finally headed to the U.S. Senate after his Republican opponent conceded Tuesday almost eight months after Election Day.

Norm Coleman, the incumbent senator from Minnesota, offered his congratulations to his Democratic rival on Tuesday afternoon after the state's Supreme Court rejected his challenge of a recount in January that gave Franken a lead of 225 votes.

Earlier Tuesday, the court ordered Franken be certified as the winner of the disputed Senate race.

The recount reversed November's unofficial Election Day results, which showed Coleman with a 215-vote lead in a race where more than 2.9 million votes were cast.

Coleman's challenge centred on whether state election officials unjustly rejected thousands of absentee ballots.

A spokesman for Senate majority leader Harry Reid said the earliest Franken would be seated is next week because the Senate is out of session for the July 4 U.S. Independence Day holiday.

With Franken seated and the usual backing of two independents, Democrats will have a majority that is large enough to overcome Republican filibusters in the Senate.

With files from the Associated Press