The Associated Press uncalled the Senate race at about 9 a.m., saying they had prematurely declared Coleman the winner.
Franken said this morning that he intends to exercise his right to a recount.
He also said his campaign is investigating alleged voting irregularities at some polling places in Minneapolis, and that “a recount could change the outcome significantly.”
“Let me be clear: Our goal is to ensure that every vote is properly counted,” he said.
Coleman will speak to reporters this morning at his headquarters in St. Paul.
Secretary of State Mark Ritchie, a Democrat, said today that a recount wouldn’t begin until mid-November at the earliest and would probably stretch into December, the Associated Press reported.
It would involve local election officials from around the state.
“No matter how fast people would like it, the emphasis is on accuracy,”
Ritchie’s office ran a speedy recount in September of a close primary race for a Supreme Court seat. That took just three days, but Ritchie said the Senate race is entirely different.
“Having a ton of lawyers and other partisans injected into the process, that will change the dynamics of it,” Ritchie said.
Both candidates captured 42 percent of the vote. Independence Party candidate Dean Barkley captured 15 percent of the vote.
Exit polls showed that Franken was helped by a wave of Democrats -- including large numbers of first-time voters -- who had already delivered the state's electoral votes to Democratic President-elect Barack Obama.
But Franken struggled throughout the evening to hang on to all of the Democratic surge, losing some to ticket-splitters who opted for Coleman, particularly in the suburbs.
Returns showed Barkley trailing a distant third, but also pulling enough Democrats and independents to possibly cost Franken the race.
The economy, which was a major factor in Obama's win, proved far less decisive for Franken. Despite making a nearly identical pitch and linking himself often with Obama in the closing days of the race, Franken was barely holding his own on that issue against Coleman, exit interviews showed.
Franken, a comedian and first-time candidate who began his effort to unseat Coleman nearly two years ago, had run behind Coleman for much of the campaign but edged ahead in some polls after the stock market imploded in late September.
Coleman had started the race as one of the GOP's three most vulnerable senators and carried the burden of being linked to both an unpopular war and an immensely unpopular president.
Barkley, who jumped into the race in mid-July, at first showed surprising strength as voters disenchanted with Coleman and Franken turned to the third-party candidate.
Contrary to earlier indications, the exit polling showed that Barkley made a bigger dent in Franken's support, pulling slightly more Democrats than Republicans into his camp. As an indication of the damage done by constant attacks, nearly half of Barkley's supporters indicated in exit polls that had he not been in the race, they would have skipped voting in the Senate contest.
By 11:30 p.m., both Coleman and Franken had addressed packed crowds of supporters, expressing optimism in a race that had taken nerves to their rawest edge.
"There is more counting to be done," Coleman said. "Keep being hopeful. I'm feeling very good right now."
Franken gave his crowd a quizzical look and cracked off a line that prompted a laugh: "What, you thought this was going to be easy?"
He expressed his pride in Obama's win and said that while it might take until mid-morning today, "I believe we're going to celebrate a victory in this race, too."
Eager for any edge, Coleman and Franken continued to hammer at voters through Election Day, wringing out the last bits of support even as they lobbed a few last-minute attacks on radio and TV.
Franken's day started shortly after dawn, with radio interviews and retail politicking that took him from Hell's Kitchen, a popular Minneapolis eatery, to St. Paul's Grand Avenue. By late afternoon, he called a timeout to toss a football around with son Joe.
As he did in 2002, Coleman closed out the race with a barnstorming, 36-hour bus tour of Minnesota that had him greeting voters at an all-night coffee shop in Brainerd at 1:30 a.m. before pulling into his St. Paul campaign office just as polls opened.
Barkley had the most low-key day of the three, with one speaking engagement and nine holes of golf in Plymouth.
A long, rocky road
The Senate race has been one of the ugliest Minnesotans have ever witnessed, with two major combatants who demonstrated early on that they would pull no punches.
National Republicans started to pick at Franken early on, characterizing him as an angry, over-the-top liberal whose edgy political humor made him "unfit for office."
Franken made the race a referendum on Bush, arguing that Coleman had helped the outgoing president "drive the economy right into the ditch."
The flaming rhetoric on both sides was fueled by an unprecedented influx of cash -- nearly $50 million -- that was unmatched by any Senate race in the country.
Some notable stumbles marked the Senate campaign trail. Franken was confronted with the discovery that he faced fines in New York and California related to his business.
He also found that he had failed to pay the proper tax on income earned in 17 states, although Franken contended that he had simply paid the taxes to the wrong states.
Those revelations, along with a continual stream of lewd humor bits unearthed by Republican operatives, nearly unraveled Franken's campaign before he even was endorsed by the DFL.
Confronted with a growing wave of disenchantment within his own party, Franken apologized for some of his cruder humor from the DFL convention stage.
Coleman had setbacks of his own. News that he was renting a bedroom and bath for $600 a month in a pricey Capitol Hill rowhouse owned by a friend and political operative raised questions about a possible gift ban violation. Coleman denied any impropriety.
Late in the campaign, a top Coleman benefactor, Nasser Kazeminy, made the news after accusations that he bought the senator's clothes and had tried to channel $75,000 from a Texas business to the senator through his wife. Coleman fiercely denied both allegations.
If elected, Franken would be the first professional comedian in the Senate.
Should Coleman return, he will have positioned himself as a coalition-builder who could prove pivotal in a Senate where Democrats are expected to fall just short of the filibuster-proof majority they sought.The Associated Press contributed to this report.