It didn't take long after the election for even staunch conservatives to start changing their tune on immigration. Days after the election, even conservative TV host Sean Hannity said he would support an immigration bill.
Said Barbour: "If we would be for good economic policy in terms of immigration, that would go a long way toward solving the political problem."
It's not just Hispanics.
Republicans said they also have work to do with single women and younger voters, many of whom tend to be more liberal on social issues than the current Republican Party. These Republicans said a change in tone is needed, though not a change in principles such as opposition to abortion.
"We need to make sure that we're not perceived as intolerant," said Ron Kaufman, a veteran Republican strategist who advised Romney's campaign. "The bottom line is we were perceived to be intolerant on some issues. And tone-deaf on others."
Republicans also said the party has to work on its relationship with working-class voters.
"Republicans have to start understanding that small business and entrepreneurs are important, but the people who work for them are also important," said Rep. Charles Bass, R-N.H., who lost his seat to Democrat Ann Kuster. "We've got to be compassionate conservatives."
Party leaders also said the GOP needs to change how it communicates its message. Obama's campaign, they said, was particularly effective at talking directly to voters, and building relationships over long periods of time, whereas the GOP was more focused on top-down communication such as TV ads and direct mail.
"There are whole sections of the American public that we didn't even engage with," Gingrich said.
Others pointed to the pressing need to recruit candidates who know how to stick to a carefully honed message, especially in a Twitter-driven era. Among their case studies: Senate candidates Richard Mourdock in Indiana and Todd Akin in Missouri, who both discussed rape and pregnancy during the campaign, to the chagrin of party leaders looking to narrow the Democrats' advantage among women.
"We need candidates who are capable of articulating their policy positions without alienating massive voting blocs," said Kevin McLaughlin, a Republican operative who worked on several Senate races for the National Republican Senatorial Committee.
Many Republicans say the party doesn't have a choice but to change — and quickly.
Said Kaufmann: "In this business, either you learn and grow or you die."
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