WASHINGTON (CNN) -- Rep. Tom Tancredo abandoned his long-shot bid for the Republican presidential nomination Thursday and endorsed Mitt Romney's candidacy, saying the Massachusetts Republican "can go the distance."
Tancredo, a Colorado Republican, is a fierce proponent of stricter illegal immigration laws, but his campaign struggled to gain traction with Republican primary voters, despite many naming illegal immigration as a top concern.
Noting the "incredibly long odds" when he launched his White House bid, Tancredo said his campaign achieved what it meant to do: put illegal immigration on the national agenda.
"I am ecstatic about the fact that we can say we have made remarkable progress along those lines," Tancredo said during a press conference in Des Moines, Iowa. "According to Newsweek, the Tancredo campaign has already won." Watch Tancredo warn of the 'perilous consequences' of illegal immigration »
After announcing he was dropping out of the race, Tancredo endorsed Romney's presidential bid, saying that Romney supported his stance on illegal immigration and national security and that the former Massachusetts governor could win the presidency.
An NBC/Wall Street Journal poll released Wednesday night showed the congressman registered less than 1 percent support nationally, and a CNN/Opinion Research Corporation poll of likely Iowa caucus-goers released Thursday put Tancredo at only 3 percent.
Of the likely Republican Iowa caucus-goers interviewed for the poll, 20 percent said immigration was the most important issue in deciding who they will support. Only caucus-goers who cited economic issues as their biggest concern was a larger group at 25 percent.
Earlier this week, Rep. Steve King of Iowa, a friend of Tancredo's who shares his tough approach on immigration, announced he was backing former Sen. Fred Thompson of Tennessee instead.
While he has not risen in the polls, Tancredo did affect the GOP by keeping the immigration issue front and center in the GOP debates he participated in.
During the CNN/YouTube debate in November, Tancredo said the candidates were "trying to out-Tancredo Tancredo" by arguing for strengthened border security, stepped-up enforcement on immigration laws and punishment of employers who hire illegal immigrants.
"That is exactly right: The other Republican candidates adopted Tancredo's tough line on illegal immigration," CNN senior political analyst Bill Schneider said. "What happens when you out-Tancredo Tancredo? You don't need Tancredo any more." E-mail to a friend