State Senate Minority Leader Josh Penry of Fruita
Why he'd run: Penry has long been talked about as candidate for governor in 2014, but if Ritter looks weak, he might move up his timetable by four years.
Why he wouldn't: It'd be difficult at best to run for governor while minority leader, so Penry may have to decide whether it's worth risking his leadership position to run. He may also hesitate if Scott McInnis, his former boss and a political mentor, enters the race.
Former U.S. Representative Scott McInnis of Grand Junction
Why he'd run: McInnis told the Denver Post last week he's interested in facing Ritter. Many GOP centrists have urged him to run for office.
Why he wouldn't: McInnis isn't exactly a darling of the state Republican party leadership (exhibit A: his aborted U.S. Senate campaign). Out of political office for four years, McInnis has appeared interested in jumping back into politics--but he has to decide if running for governor is the best way to return.
Former U.S. Representative Tom Tancredo of Littleton
Why he'd run: Tancredo's dropped strong hints that he would run for governor after last year's general elections.
Why he wouldn't: Many Republicans are frightened that Tancredo, a leader in the anti-immigration movement, would poison their party's relations with Latino voters for years to come.
2006 GOP gubernatorial nominee Bob Beauprez of Lafayette
Why he'd run: Beauprez said earlier this month that he's considering a run for either governor or U.S. Senate.
Why he wouldn't: He already lost to Ritter once. It remains to be seen if he can convince Republicans to give him a second shot.
2006 GOP gubernatorial candidate Marc Holtzman of Carbondale (not pictured)
Why he'd run: Having lost one chance at facing Ritter in 2006, Holtzman might see better odds for himself in 2010.
Why he wouldn't: As a vice-chairman of London-based Barclays Capital, Holtzman spends a large part of his time out of Colorado. That's not helpful for someone trying to build a campaign. He and his wife also had a baby recently.
Former state SenatorÂ Tom Wiens of Castle Rock
Why he'd run: Wiens had been showing interest in a 2010 gubernatorial run even before he left the state Senate, and he's already looking to assemble a campaign staff. Holding millions in hotel, banking, and real estate, Wiens would likely be the richest candidate in the race.
Why he wouldn't: Rumors have circulated that Wiens is having financial problems. While those rumors haven't been confirmed, Wiens might decide to tend to his business interests instead of running.
Businessman Cleve Tidwell of Denver (not pictured)
Why he'd run: This political unknown has started to make appearances at Denver GOP events, saying he's considering a gubernatorial run.
Why he wouldn't: He might opt instead to run for Diana DeGette's First Congressional District seat in 2010.
Former U.S. Senator Hank Brown of Denver
Why he'd run: Brown's making the rounds at GOP events, giving speeches and being visible. His political centrism and focus on economic issues might play well next year.
Why he wouldn't: If social issues once again become a major issue in the GOP primary, that wouldn't play to Brown's strengths.