Tellingly, a path to citizenship is backed by 69 percent of nonwhites, including 80 percent of Hispanics and 67 percent of blacks – groups that overwhelmingly favored Barack Obama in his successful re-election campaign. That falls to 51 percent of whites, who preferred Republican Mitt Romney by 20 points.

There’s also a sharp generational break in this poll produced for ABC by Langer Research Associates: Adults younger than age 40 – a group that decisively favored Obama over Romney in the election – back a path to citizenship by 67-30 percent. Support drops to a bare majority, 51 percent, among those 40 and up, a majority of whom voted for Romney.

Those differences underscore the challenges facing Republican Party leaders: Stay loyal to the policy preference of their party faithful and core support groups including whites, older adults and conservatives, at the risk of clinging to an inadequate support base; or seek to appeal to groups such as Hispanics, younger adults and moderates, at the risk of alienating the party’s core.