Former Republican senator Norm Coleman gave up his fight for the U.S. Senate on Tuesday, congratulating rival Al Franken after Minnesota's highest court upheld a decision by a lower court declaring Franken the winner in last November's election.

After Coleman was initially declared the winner by a narrow margin of a few hundred votes, a recount gave Franken the win by 312 votes with 2.4 million ballots cast.

I just had conversation with Al Franken congratulating him on his victory, Coleman said during a press conference today outside his home in St. Paul, according to Associated Press video.

Coleman chose not to pursue an appeal to a federal court.

We have reached the point where further litigation damages the unity of our state, Coleman said.

I conducted the legal challenge I wanted. I have always believed you do the best you can and you leave the results to a higher authority. I'm at peace with that, he added.

Minnesota's Supreme Court today upheld an April ruling which declared Franken won by 312 votes.

We affirm the decision of the trial court that Al Franken received the highest number of votes legally cast and is entitled ... to receive the certificate of election as United States Senator from the State of Minnesota, the Court stated in its opinion, released to the web.

See selected highlights by Coleman and the court's ruling below.