Last week's Gallup poll finds 3% of respondents believe immigration is "the most important problem facing this country today." The top five responses were dissatisfaction with government, the economy in general, healthcare, unemployment, and the Federal budget deficit.
President Obama's recently identified priority for the balance of his term - the gap between rich and poor - was most important to only 2% of respondents. Assuming (a) Gallup got good data and (b) public attitudes don't change dramatically, the GOP can afford to ignore immigration reform almost indefinitely.