Republicans have three days to make up their minds in a handful of contested primaries throughout the state and county, and the political frenzy has arrived as candidates make last-ditch efforts to sway voters.
"Advertising has sort of ramped up," said pollster and political analyst Floyd Ciruli.
Perhaps most noticeable in the last-minute media melee are the attacks against gubernatorial candidate Tom Tancredo, and a TV ad produced by Rep. Doug Lamborn going after his 5th Congressional District opponent, Bentley Rayburn.
Tancredo has become a target in the four-way race for governor ever since a poll was leaked by one of his opponents showing the former congressman had a slight lead in the race. Republicans have been attacked the positions Tancredo has taken on gun laws and marijuana legalization.
Likewise, liberal groups, who see Tancredo as a good match against Democratic Gov. John Hickenlooper in November, have run thinly veiled attack ads that actually make Tancredo look better to conservative voters and make former Rep. Bob Beauprez look worse.
"There's a general sense out there that this is a very close race, particularly between Beauprez and Tancredo," Ciruli said. "There are a lot of votes out there to come in yet, and that's why the advertising is so intense."
Each registered GOP voter in the state received a ballot in the mail early in June, and 238,906 ballots have been returned, according to numbers released Friday by the Secretary of State's Office.
Ciruli said in 2010 - the last time there were Republican governor and congressional primaries on the ballot - about 400,000 voters turned out, indicating either that there are a lot of people still making up their minds or turnout will be lower.
A low turnout, he said, could benefit Tancredo because he has a loyal base of active voters.
But Ciruli said he wouldn't count out former State Senate Minority Leader Mike Kopp, who is praised in a radio ad that also rails against Tancredo's support of legalizing marijuana. The ad is tied to former U.S. Sen. Bill Armstrong.
"My sense is that Kopp got a late surge," Ciruli said. "Bill Armstrong is among the most powerful endorsements you could get. It's a good issue. It's good for Kopp, and I think it hurts Tom Tancredo."
Secretary of State Scott Gessler, was once a front-runner in the campaign and had impressive fundraising numbers leading up to the primary, but Ciruli said "in the past two weeks he's disappeared."
Meanwhile, the negative ads could actually boost Tancredo among his conservative base.
"Those folks are anti-establishment. They love the fact that he is a renegade and a maverick," Ciruli said.
And all of the uncertainty means it's still anyone's game heading into Tuesday's elections.
That might also be the case in the 5th Congressional District race, where Lamborn and Rayburn are battling to represent El Paso, Teller, Fremont, Chaffee, Lake and part of Park counties. The winner of the primary will face retired Maj. Gen. Irv Halter, a Democrat, in November.
"It's extraordinarily difficult to defeat an incumbent member ofCongress," said Steve Durham, a long-time El Paso County Republican who served in the Colorado House and Senate and is now a lobbyist and consultant. "While this race might be closer than previous races, it would be a significant surprise if (Lamborn) were to lose."
Durham said polling indicates the race is closer than others Lamborn has faced - in 2012 he defeated Robert Blaha in a primary 61 percent to 39 percent. And Lamborn has defeated Rayburn in two other primaries.
"When I first heard that Bentley was going to run, I concluded that he must be either a slow learner or very persistent," Durham said. "There's also a message for Lamborn. He seems to have a challenge virtually every time. He needs to do a better job producing results for the party . and specifically he needs to raise money for the party. He needs to be a net contributor, not a net taker."
But Patrick Davis, a Republican political consultant with Colorado Springs-based Patrick Davis Consulting, said this is a completely different race than Lamborn has faced before.
"Neither of them have been in an environment where every Republican gets a ballot," Davis said. "Doug Lamborn has never had to face this large of an audience. That to me is a real disadvantage."
But he said for Rayburn to have a chance, the retired two-star general needs to not only make a case for why Lamborn should be fired, but for why voters should put him in office.
"He may have successfully made the first case, but I don't know if he had enough resources and time to get himself hired," Davis said.
Rayburn went negative from day one, winning a spot on the ballot with a stirring speech at the Republican assembly, where he attacked Lamborn's record.
Lamborn has gone negative more recently, running a TV ad that accuses Rayburn of supporting cuts to the Department of Defense and never fighting the Affordable Care Act.
"I do think that he's worried," Davis said. "These attacks on Gen. Rayburn, going right at him for things that are clearly not true, he's throwing everything up against the wall to see what sticks."
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