BOULDER, Colo. -- Incumbent Democrat Michael Bennet
defeated Republican challenger Ken Buck
by more than 15,000 votes in one of the most heated Senate contests in the nation.
"This election was always about our hopeful, strong future of our beautiful Colorado," Bennet said. "It was about and it is about making sure that our generation lives up to the promise of America... that's not a Democratic idea or a Republican idea, that is an American idea."
Bennet vowed to rise above partisanship on his return to Capitol Hill.
"I'm not going back to Washington to play politics, I'm going back to fight for more jobs and better jobs, to fight for a new energy economy and a better education for our children."
Buck called Bennet to offer his congratulations late Wednesday afternoon. "My Senate campaign has been the experience of a lifetime," Buck said in a prepared statement. "I will be forever grateful to the thousands of Coloradans who helped make this grassroots journey possible."
With more than 97 percent of precincts counted, Bennet's 48 percent to 47 percent lead appeared to be recount proof. Colorado law would require a margin of less than 4,000 votes to trigger an automatic recount.
The Denver Post declared Bennet
the winner early Wednesday. The Associated Press called the race for Bennet Wednesday afternoon.
The evening began with Bennet leading, but as conservative Colorado Springs and rural areas reported results, Buck took a narrow lead. Neither candidate appeared before supporters Tuesday evening, instead staying sequestered in hotel rooms.
Republicans have already picked up six U.S. Senate seats, slicing into the Democratic majority on Capitol Hill. However, Democrats were guaranteed of keeping a narrow edge, even with a victory by the conservative Buck in Colorado.
The Senate contest ranked No. 1 in the nation for the sort of outside spending
made possible by the Supreme Court's Citizens United ruling
earlier this year.
Of the more than $30 million spent
during the general election, $10.8 million was for negative ads against Bennet while $11.3 million went for negative campaigning against Buck. The GOP candidate saw $3.3 million in external spending supporting his candidacy compared with $1.4 million for Bennet.
Bennet raised almost $11.5 million through Oct. 13, compared with Buck's $3.8 million take, according to the Federal Election Commission.
and his supporters attacked Bennet on his support for President Barack Obama's financial policies and health care reform. Bennet
and his allies charged that Buck is "too extreme" attacking his opposition to abortion in cases of rape and incest, as well as his failure to prosecute
a 2005 acquaintance rape case.
Both candidates won brutal primaries. Dubbed the "accidental senator" by the state GOP, Bennet was Gov. Bill Ritter's surprise pick to replace Ken Salazar in January 2009 after Obama named Salazar Interior secretary.
"Gov Ritter 22 months ago made a very surprising choice," Bennet said Wednesday. "Most people thought he'd lost his mind. I want to thank Gov. Ritter for believing in me then and thank you Colorado for believing in me now."
Despite plenty of negativity, Bennet won the primary with 54 percent of the vote.
Buck benefited from outside spending from GOP Sen. Jim DeMint's PAC and other groups as well as tea party enthusiasm propelling Buck to a narrow victory with 51.5 percent of the vote over his opponent.
The Weld County prosecutor made some verbal missteps along the campaign trail. Most notable, Buck said during a "Meet the Press"
debate that he believed homosexuality is a choice.
Bennet found himself trying to justify his vote on the $787-billion stimulus package in 2009, and this fall announced
he wouldn't support another, smaller bill proposed by the president. Obama came to Colorado in February to raise money for the former Denver Public Schools superintendent, but didn't make his presence felt in the general election. Michelle Obama held a fundraiser for Bennet in mid-October, while former President Bill Clinton held a rally for the candidate later in the month.
Video: Michael Bennet Interview
Ahead of the election, Sen. Michael Bennet spoke with Politics Daily Executive Editor Carl Cannon about Colorado politics and his Republican opponent Ken Buck. Watch highlights below and click here for more about their conversation.