Bennet has scheduled a victory press conference for later today, though Buck is not conceding.
"We are still looking where returns need to be reported, as well as provisional ballots before making any decisions," Buck spokesperson Owen Loftus told 9NEWS in a statement. "We will have further comment later today."
After Buck and Bennet each won hard-fought primaries in August, it looked for awhile like Buck was going to run away with the general. Though Bennet was only appointed to the Senate in 2009, after then-Sen. Ken Salazar was named Secretary of the Interior, Bennet was still the incumbent, and Buck and groups supporting him tied Bennet to President Obama and the Democratic Party's political liabilities: the stimulus, the bailouts and health care.
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But then, in the weeks leading up to election day, Buck seemed to falter. He committed a number of high-profile gaffes. On Meet the Press, he compared being gay to alcoholism. He was perceived as weak on women's issues -- a narrative that was fueled by the fact that polls showed Buck trailing Bennet by a wide margin among women. A rape case Buck declined to prosecute as the Weld County District Attorney in 2005 resurfaced in the news, and much was made of a comment he made to a newspaper at the time, that the case could have been perceived by a jury as a case of "buyer's remorse." In the final days, polls showed the gap between the candidates shrinking.
From early on, the Bennet campaign and Democratic groups tried to paint the Tea Party-backed Buck as "too extreme" for Colorado, and of a piece with candidates like Sharron Angle, Christine O'Donnell and Rand Paul. Buck also had to answer for switching positions on a number of issues. His change of heart on the "personhood" amendment (at first he supported the controversial pro-life measure, but he withdrew his support after the primary) drew scorn from pro-choice and pro-life groups. He had dust-ups with constitutional amendments. He was videotaped at a campaign event disparaging the 17th amendment, which allows for the direct election of Senators. Another video showed him saying he strongly disagreed with the separation of church and state. All together, these moments may have kept Buck from locking up the race in a Republican-leaning year.
Outcome aside, the defining feature of this campaign was spending by outside groups. Colorado was flooded with ads from interest groups, and this race ranked number one in the country -- by far -- in total spending by interest groups and political parties, according to the The Washington Post. The Post reports that $33.4 million was pumped into the state, 54% by Republican or Republican-supporting groups. The next races on the list, according to the Post, were the Pennsylvania Senate race, with over $25 million in spending, and the Washington Senate race, with over $18.5 million.
Leading the way in Colorado were the Democratic Senatorial Campaign Committee (over $7.5 million), American Crossroads (over $6 million), the National Republican Senatorial Committee (over $5 million), the U.S. Chamber of Commerce (over $2 million) and the National Education Association (over $1.8 million). All told, nine groups spent more than $1 million on the race. These and other groups spent over $7.5 million in just one week two weeks ago. According to the Post, that's more than the total amount spent on the Florida Senate battle between Gov. Charlie Crist (I), Marco Rubio (R) and Kendrick Meek (D).