WASHINGTON -- GOP Rep. Cory Gardner's decision to challenge Democratic incumbent Mark Udall has shaken up the U.S. Senate race and energized state and national Republicans.
Now comes the hard part -- the Yuma Republican has to deliver the goods.
Telegenic and articulate, Gardner is seen as a rising GOP star and the party's best hope to unseat Udall, who until now was considered a shoo-in to win re-election.
But Gardner faces a tough climb. He has far less campaign cash than the incumbent, is little known outside state GOP circles and the 4th Congressional District and lacks Udall's storied family name and statewide recognition, analysts say.
Going into 2014, Gardner had raised less than $1 million in this election cycle and had nearly $900,000 in his campaign account, according to the Federal Election Commission.
He faces at least one challenger in the June 24 GOP primary -- tea-party backed state Sen. Owen Hill -- whereas Udall has no Democratic primary opposition.
FEC records show Udall has raised more than $5 million in this election cycle and had $4.7 million in cash as of Dec. 31.
He's stepping up his fundraising pace, with at least six events in March in Washington, Miami, New York City, Texas, Phoenix and Seattle, according to invitations obtained by the Sunlight Foundation.
Udall can also count on the Democratic Senatorial Campaign Committee's support. Sen. Michael Bennet, Colorado's junior senator, heads the group, which raises money for incumbents and Democratic candidates across the country. The DSCC faces a tough battle because it has 21 seats to defend, compared to 14 for the National Republican Senatorial Committee.
Kyle Saunders, a Colorado State University political scientist, said Friday that Gardner needs to raise $10 million or more to be competitive in the race.
Gardner, who refused to run when approached last year, may have waited too long to jump into the race and may not have enough time to make up the cash difference, Saunders said.
"He's at a big disadvantage with regard to the money. The question becomes can he set up the infrastructure and have the backing of not just (national Republicans) but also raise his own money to close that gap?" Saunders said.
And money is not even his biggest hurdle, Saunders said.
"His main challenge is going to be somehow convincing . . . independent voters to actually think that he's not a very conservative Republican," he said.
Gardner is scheduled to launch his Senate bid Saturday in Denver. His campaign declined to comment before then.
Floyd Ciruli, a pollster who does surveys for 9NEWS, said Gardner should have little trouble raising money if he can prove to wealthy donors that he can make inroads among Colorado's independent voters.
His entry has put the Colorado Senate race in play, an attractive proposition for big donors and GOP-affiliated independent groups that face no spending limits in their bid to influence election outcomes.
Republicans need to pick up six Democratic seats to regain control of the Senate. Alaska, Arkansas, Louisiana, North Carolina, Montana, South Dakota and West Virginia were considered their best chances until Gardner's announcement added Colorado to the mix.
Republican Weld County Commissioner Sean Conway, who's considering running for Gardner's House seat, said Gardner has begun raising a lot of money because donors recognize that he represents the GOP's best chance to beat Udall.
"As the old adage goes, you can't beat somebody with no one," said Conway, who served as former Colorado Republican Sen. Wayne Allard's chief of staff and was Gardner's boss when Gardner worked for Allard. "We now have someone. Cory Gardner is probably not just one of the great rising stars in the Colorado Republican Party but also nationally."
Udall's poll numbers have been unimpressive because of a host of factors, analysts say. His support for the unpopular Affordable Care Act, the botched rollout of the health-care enrollment web site and President Barack Obama's sagging approval numbers are all contributors.
Surveys done in early February by Quinnipiac University -- before Gardner entered the race -- showed Udall barely ahead of Ken Buck and lesser-known GOP challengers. Buck, who lost his 2010 Senate bid to Bennet in what was a banner year for tea-party candidates, was regarded as a weak candidate to take on Udall.
In a move Democrats and GOP candidate Hill say reeks of backroom politics, Buck withdrew from the Senate race to run for Gardner's House seat instead.
Chris Harris, Udall's campaign spokesman, refused to say how much Udall has raised this year. He said Udall is confident he'll have enough money to prevail in November in what's sure to be an expensive, bitter fight with plenty of participation by outside groups.
"We are doing our best to prepare for a barrage of attack ads," Harris said.
The candidate who wins the independent vote will win the race in fiercely independent Colorado. According to January voter registration statistics from the state, Colorado has 1.3 million unaffiliated voters compared to 1.11 million registered Democrats and 1.12 million registered Republicans.
"Congressman Gardner's entry doesn't change the fundamental dynamics of the race," Harris said. "We've always known that this is going to be a competitive race. Colorado is a purple state. Coloradans vote for the person, not the party."