U.S. Rep. Cory Gardner, R-Colo., speaks after retaining his seat in Colorado's Fourth Congressional District during a Republican Party election night gathering in the club level of Sports Authority Field at Mile High in Denver on Tuesday, Nov. 6, 2012. (AP Photo/David Zalubowski)

The Service Employees International Union launched a series of Spanish-language ads on Tuesday going after House Republicans for their failure on immigration reform, specifically targeting four lawmakers who had previously expressed openness to working on the issue.

The television ads will air for two weeks in the districts of Reps. Mike Coffman (R-Colo.), David Valadao (R-Calif.), Joe Heck (R-Nev.) and Cory Gardner (R-Colo.). All four men were initially considered potential supporters of immigration reform -- Valadao even joined with Democrats in supporting a comprehensive bill -- but in the end, those efforts went nowhere.

SEIU Executive Vice President Rocio Saenz said Republicans are to blame for blocking immigration reform, and the four members targeted in the ad must be held accountable as part of their party.

"The excuses, the blatant anti-immigrant rhetoric and their unwillingness to vote for immigration reform have made it abundantly clear to us all that Republicans are not interested in creating inroads or addressing the concerns of the Latino and immigrant community," Saenz said in a statement. "Republicans cannot hide behind irrational pretexts or lawsuits -- we're calling them out on the most important issue for the fastest-growing electorate in our country."

"Congressmen Coffman, Gardner, Valadao and Heck are all part of a Republican Party that must face a large constituency of Latino voters and be held accountable to their party's consistent catering to anti-immigrant extremists," she continued.

The ads feature a narrator quoting her grandmother as saying, "Tell me who you're with, and I'll tell you who you are."

"Why? Because Republicans again and again insult our community, and blocked immigration reform," the narrator continues, as translated by SEIU. "And the worst: They have voted against our future and our Dreamers. This November, we must go to the polls and vote against Republicans."

All four congressmen are from districts with large Latino populations. Gardner, who is running for the U.S. Senate this November, faces a substantial Latino vote in his statewide race.