Republican Senate candidate Ryan Frazier had his nominating petitions approved by the Colorado secretary of state’s office on Monday, The Colorado Statesman has learned. He’ll have just over two months to gather sufficient signatures to make what could be a crowded primary ballot.

Eleven other GOP hopefuls have announced they’re running for the chance to challenge Democratic U.S. Sen. Michael Bennet, making Colorado’s contest the most crowded primary field in the country.

Candidates can petition on to the June 28 primary ballot or qualify at the GOP state assembly by winning the support of at least 30 percent of delegates.

Frazier, a former Aurora city councilman, will need 10,500 valid signatures, including 1,500 from each of the state’s seven congressional districts. Campaigns can start circulating the petitions on Feb. 1 and must turn in completed petitions by April 4.

State Sen. Tim Neville, R-Littleton, and El Paso County Commissioner Peg Littleton have both pledged to pursue the nomination through the caucus and assembly process, while the campaigns of former state Rep. Jon Keyser, R-Morrison, and Colorado Springs businessman Robert Blaha have said they’re still deciding which route to take.

Other candidates in the race include El Paso County Commissioner Darryl Glenn, Jefferson County Commissioner Don Rosier, Charlie Ehler, Tom Janich, Michael Kinlaw and Jerry Eller. Hispanic business leader Jerry Natividad has said he’s planning to announce his candidacy by the end of the month.

Frazier announced earlier this month that he raised $200,000 in the last seven weeks of 2015, although he didn’t say how much he spent or how much cash he had on hand. Bennet’s campaign said last week that the Democrat raised nearly $2 million in the final quarter of 2015 and has more than $6.7 million in the bank. The deadline to file end-of-year FEC reports is the end of January.

Frazier, who ran for the Senate briefly in 2010 before switching to challenge U.S. Rep. Ed Perlmutter, had the highest name ID and led other major candidates in a preliminary match-up released by his campaign earlier this month. According to a robopoll of likely Republican voters, Frazier had the support of 18 percent of respondents, followed by Neville at 7 percent, Blaha at 6 percent, Glenn at 5 percent and Keyser at 4 percent, although a full 60 percent of those surveyed were undecided. The survey had a margin of error of plus-or-minus 4.03 percent, the pollsters said.

— ernest@colordostatesman.com