The mood seems buoyant. A simple recitation of the Pledge of Allegiance draws cheers when one woman supplements the final words "with liberty and justice for all" with "including the unborn."
Several elected officials (led by state Rep. Kent Lambert and County Commissioner Wayne Williams) and selected faithful fire up the crowd by touting Lamborn's record as a rep. His place on the House Armed Services Committee gives him power, they say, and some consider his voting record the most conservative in Congress.
Few seem inclined to spoil the mood by looking ahead to what could be a bruising primary battle for the Republican nomination. Lamborn will likely face two of his main rivals from the six-way race he barely won in 2006.
One woman speaks of Lamborn's accessibility and devotion to constituents before briefly noting, "I am so sorry we are going to have another divisive battle."
Many in Lamborn's six-county district, though, are likely tickled. Jeff Crank, a top aide for Rep. Joel Hefley in the '90s, announced his candidacy in November. He missed the GOP nod for his old boss' seat by only a few hundred votes in '06.
Retired Maj. Gen. Bentley Rayburn, who finished third in the 2006 primary, is also taking another shot. Saying the caucus system has helped create divisions in the party, Rayburn has announced plans to put his name on the Aug. 12 primary ballots by collecting 1,000 signatures.
Since beating Democrat Jay Fawcett in the 2006 general election, Lamborn has earned criticism for everything from sending too many constituent mailings to apparently making threatening calls to a couple supporting a rival.
El Paso County Commission Chair Dennis Hisey, who has not given an endorsement, mentions that Lamborn only managed to attract a couple dozen colleagues to his side as the House overwhelmingly voted to suspend further study of a proposal to expand Fort Carson's training grounds at Pion Canyon.
"That kind of tells you his clout," Hisey says.
A similar dissatisfaction is apparent in other parts of the district, which, in addition to El Paso County, includes Teller, Chaffee, Fremont and Lake counties, as well as part of Park County.
Melissa Scott, one of two vice chairs of the Chaffee County Republican central committee, declines to state her own preference among District 5 contenders, but says she's noted a trend in her party. Late last year, she says, most had wanted to avoid a contentious primary fight.
Weeks later, many were talking about the candidacy of Jeff Crank.
"They don't feel like [Lamborn] has represented this part of the district," Scott says.
Lamborn, speaking to supporters Monday night, suggests instead that his opponents could only take the seat leftward. He speaks proudly of voting against the Democrats 99.3 percent of the time.
I dont think that gives my opponents much to run on, he says.
Candidates have three basic options for getting their names on the Aug. 12 primary ballot, and going by straight petition is one of them.
Local party officials have stated a preference that candidates go through the caucuses. Delegates from the 5th district selected at Tuesday's caucuses will vote among candidates going that route at a Republican assembly May 30.
Candidates getting more than 30 percent of the vote will go on the ballot. Those getting 10 to 30 percent will still need to petition. Those getting less than 10 percent will be kept off it.