Mr Coleman (left) has pledged to fight Mr Franken in the courts
A recount in the US state of Minnesota has confirmed its Senate seat was won by Democratic candidate Al Franken but the result is still being contested.
Mr Franken's Republican opponent, Norm Coleman, has seven days to challenge the result in the courts.
No-one will be declared a winner until Mr Coleman's legal fight is complete.
When the votes were first tallied, Mr Coleman led Mr Franken by 215 votes but after the lengthy and controversial recount, Mr Franken led by 225.
The manual recount was automatically triggered because Mr Coleman's winning margin was less than 0.5% of the vote.
During the recount, Mr Franken picked up a number of votes because manual recounters were able to determine the intent of voters overlooked by vote-counting machines.
If Mr Franken, a satirical comedian and radio host, is eventually declared the winner, the Democrats will control 59 votes in the Senate.
The party needs 60 votes in the chamber to overturn a filibuster - a blocking tactic used by the Senate minority to prevent legislation from coming to a vote.
Mr Coleman's legal team contends that the Minnesota canvassing board's certification of the result is incorrect because a number of absentee ballots were improperly excluded from the recount.
Tony Trimble, lawyer for Mr Coleman, has said that there "can be no confidence" in the results as certified.
But Democratic Senate Majority Leader Harry Reid called on Mr Coleman to pull out of the race.
"The race in Minnesota is over," he said.
And he described Mr Coleman's legal challenges as "only a little finger-pointing".