U.S. Rep. Doug Lamborn (R-Colorado Springs) will petition onto the CD-5 primary ballot -- a move that is very unusual for an incumbent Congressman in Colorado to make.

In an e-mail sent to supporters Tuesday, Lamborn cited his Congressional voting schedule and claiming the El Paso County GOP wasn't able to adequately monitor and track delegate information.

Campaigns for Lamborn's two primary opponents quickly dismissed those explanations, saying his real reason for petitioning was because he risked falling short of the 30 percent assembly threshold needed to make the primary ballot.

In the e-mail, Lamborn stated that he has "lost confidence that the various problems can be satisfactorily resolved by the date of the assembly and that the process in place is of the quality required for a Congressional election."

The e-mail was acquired and publicly released by the Jeff Crank campaign Tuesday.

The high turnout from the Feb. 5 GOP caucus "overwhelmed the ability of the (El Paso) county party to adequately monitor and track delegate information," Lamborn said, adding by his count he was leading among assembly delegates.

Lamborn also said his Congressional duties during April and May prevented him from contacting delegates on weekdays.

"Mailings and phone calls are helpful, but the one-on-one meetings that are the best, and that 1,200 delegates and alternates should have, are not easy to arrange during the remaining weekends," Lamborn stated in the e-mail.

The Lamborn campaign did not respond to a phone call seeking comment Tuesday afternoon.

A source close to the El Paso County Republican Party disputed that high caucus turnout "overwhelmed" the local party, saying the caucus results were reported smoothly and ahead of schedule.

With Bentley Rayburn tentatively planning to also petition, Jeff Crank may be the only CD-5 GOP candidate choosing to seek ballot access through the assembly process -- in such a scenario, Crank would be guaranteed the top slot in the primary ballot.

"I consider it a victory for our campaign," Crank said. "It's further evidence as to who the strongest candidate in this race is."

Crank said Lamborn's excuses for leaving the assembly process were "baloney," saying calls to about three-quarters of the delegates showed Crank leading Lamborn 60 percent to 30 percent. Rayburn had about 8 percent of the delegates called, Crank said.

Rayburn manager Mike Hesse rejected Lamborn's claim that his Congressional schedule didn't give him enough time to schmooze CD-5 delegates between now and the CD-5 assembly

"As the incumbent, he's had two years to work the delegates," Hesse said. "It shows very clearly that his record is severely lacking."

Hesse in his 27 years in Colorado politics, this is the first time he can recall an incumbent having to petition onto the ballot.

Hesse said Rayburn would continue his plan to petition onto the ballot, but Hesse added that "we'll kind of wait and see how things go" in the next few days.

Hesse also disputed Crank's delegate support numbers and questioned whether Lamborn's decision was a "victory" for Crank.

The CD-5 assembly would have been Crank's "big chance to create some real momentum and beat the incumbent -- and now that's been taken away from him," Hesse said.

Colorado State University political science professor John Straayer said it's "very, very unusual" for an incumbent Congressman to petition on the ballot.

Asked if it was unprecedented, Straayer said he wasn't sure.

"It's not the thing you sort of check because it's so unusual," he said.

Ken Bickers, chair of the political science department at the University of Colorado, said Lamborn choosing to petition was "a sign of political weakness.

"I find it, frankly, extraordinary," Bickers said.