Colorado Democratic Gov. John Hickenlooper, once considered a safe bet for re-election, is looking at the possibility of an upset after recent polling showed his Republican rival pulling way ahead.

Hickenlooper has dominated in fundraising and earlier this year led handily in the polls. But the race began to tighten over the summer. Now, a survey from the nonpartisan Quinnipiac University shows Hickenlooper trailing his Republican opponent, former Rep. Bob Beauprez, by 10 points.

The development comes just weeks before every registered voter receives a ballot in the mail, an option now open to voters across the state.

Though other recent surveys have shown the race closer, the Quinnipiac poll was done with "likely" voters -- this is an important distinction from other polls, which have just looked at registered voters.

"We are closer to the election. We decided to fine tune it from 'likely' to 'registered' to give you a better feel for people who absolutely will go to the voting booth," Assistant Director of the Quinnipiac University poll Tim Malloy said. He added their findings may differ from others because Quinnipiac's team calls cell phones, and not just land lines.

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Beauprez said their fight for the governor's office has become nationalized. "[Hickenlooper] seems to want to defend Barack Obama, every chance he gets. Barack Obama is not so popular in Colorado right now. So it is a referendum both on John Hickenlooper but certainly Barack Obama as well," he said.

The governor made his money with brew pubs before starting public life. The Republican Governors Association (RGA), accordingly, has run ads making hay out of Hickenlooper's love of beer and his recent night of pool with the president. Despite being under siege in a tight race, Hickenlooper is steering clear of running his own attack ads for the time being.

Hickenlooper's campaign turned down requests from Fox News for an interview, but the governor did respond to a local news crew, and downplayed the state of the race. "I don't think the [Quinnipiac] poll's right. Everyone's got one of the magic 8 balls, right, turn it over and it comes out with a different number," he said.

The governor has had a series of high-profile verbal flubs on guns and capital punishment, helping make the race so competitive. An attempted apology to Colorado sheriffs back-fired when he tried to explain why he signed some of the strictest gun control measures in the nation. Hickenlooper said his office never expected those to pass, and someone promised on his behalf he would sign off on them.

In a state working up to the death penalty trial of accused Aurora theater shooter James Holmes, Hickenlooper also has taken heat for his handling of death-row inmate and convicted killer Nathan Dunlap's case. The governor issued a temporary reprieve, putting Dunlap's execution in indefinite limbo. And he has suggested the possibility of granting clemency to Dunlap, if he fails to win re-election and finds himself a lame-duck governor.

Beauprez is capitalizing on the toll the controversies have taken on Hickenloooper's image. "John seems to forever want to kick the can down the road," Beauprez said. "That single decision [in the Dunlap case] I think crystallized John's problems, for a great many people. We kind of suddenly went from kind of cute and maybe a little bit of 'aww shucks' to, 'what's up with that?'"

Malloy said anti-incumbency fever is noticeable in states such as Colorado right now. "It's a tough time to be a candidate, it's a tough time to be an incumbent," he said. "It just is."

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