The establishment Republicans called for the party to back immigration reform as the way to start winning again. "Among the steps Republicans take in the Hispanic community and beyond, we must embrace and champion comprehensive immigration reform," it said. "If we do not, our Party's appeal will continue to shrink to its core constituencies only.... Hispanic voters tell us our Party's position on immigration has become a litmus test, measuring whether we are meeting them with a welcome mat or a closed door."

Or listen to the College Republican National Committee, which just issued a report on retooling the "Grand Old Party for a Brand New Generation."

"The issue of the Republican Party's challenges with the youth vote and the party's challenges with non-white voters are inseparable," the report said. "The immigration debate may set up a 'gateway issue.' For voters who are undecided but have a connection to communities affected by immigration policy, the issue can certainly turn voters away."

Support for the exact sort of measures House Republicans rejected today would be key, the young Republicans wrote:

On the issue of laws that "would allow illegal immigrants brought to the U.S. as children to gain legal resident status if they join the military or go to college," three out of four (75.3%) young adults agreed in an October 2012 poll conducted by CIRCLE. And young voters for the most part knew how the candidates in the election stood on that issue; in that same survey, 63% of respondents said that Barack Obama was the candidate who supported "allowing many illegal or undocumented immigrants who were brought to the United States as children to remain in the country," while only 3% said that was Mitt Romney's position.

Or listen to Karl Rove, who on Thursday warned in the Wall Street Journal, "Immigration reform is now a gateway issue: Many Hispanics won't be open to Republicans until it is resolved, which could take the rest of the year. But there is little doubt next week's Senate deliberations will shape for some time to come the Hispanic community's perceptions of the GOP."

There were boos in the House gallery when the measure to undo Obama's executive order halting deportation of young undocumented immigrants, known as DREAMers after the still unpassed DREAM Act that would provide them with a pathway to citizenship, passed on a highly partisan vote of 224-201.

While reform advocates remain optimistic about prospects for passage of the Senate Gang of Eight comprehensive immigration-reform bill, what will happen in the House remains unclear.

"We always predicted this would be a roller coaster ride with some dark moments and some strong challenges and some bad days. What makes me optimistic are the fundamentals," said Frank Sharry, executive director of America's Voice Education Fund. Speaking on a call organized to discuss new polling from his group and Latino Decisions, he noted, "The challenge that we're up against is resistance within the Republican Party and the institutional legitimacy of Congress -- can it function?...This is going to be a remarkable moment of truth for the Republican Party; they literally are facing an existential moment of truth."