In the Republican primary to succeed him, Hefley backed his long-time aide, former administrative director Jeff Crank. The election was held on August 8, 2006, with Lamborn defeating Crank and four other candidates to win the party nomination in a contentious six-way race. In the Republican primary, he ran on conservative positions: opposing gun control, abortion except when the mother's life is threatened, federal funding of embryonic stem cell research, not providing public benefits to illegal immigrants, and new eminent domain rulings.