It appears likely the Gang of Eight's comprehensive immigration reform bill will come up for a vote in the Senate this week. Most political analysts believe the controversial measure, primarily sponsored by Sen. Chuck Schumer, D-N.Y., and Sen. Marco Rubio, R-Fla., will pass the upper chamber easily. These same pundits are virtually unanimous on another point in the immigration reform debate: Republicans must support the measure if they hope to win future presidential elections.

The idea that the GOP must pander to Hispanic voters in 2013 in order to win the White House in 2016, however, ignores key facts in the Republican loss in 2012. To begin with, the failure to attract sufficient numbers of Hispanic voters was not the reason Mitt Romney lost to President Obama. As the Washington Examiner's Byron York pointed out in May, Romney could have won 70 percent of the Hispanic vote - almost exactly the reverse of the actual results - and still fallen short. Citing a statistical tool created by the New York Times' Nate Silver, York noted that "Romney would have had to win 73 percent of the Hispanic vote to prevail in 2012. Which suggests that Romney, and Republicans, had bigger problems than Hispanic voters."

What those bigger problems were is no mystery. As York put it, "Romney was not able to connect with white voters who were so turned off by the campaign that they abandoned the GOP and in many cases stayed away from the polls altogether." Had Romney attracted as much white support as George W. Bush did in his re-election effort in 2004, the former Massachusetts governor would be in the Oval Office today, according to York.

York's analysis appeared in May, when it appeared that about five million white voters had stayed home in November 2012. But Sean Trende of Real Clear Politics was able to use more complete data last week to count and identify these no-shows with greater precision. It turns out that about 6.5 million white voters were stay-at-homes. They came predominantly from an arc running roughly from New Mexico through West Texas and Oklahoma, then on across Missouri, Michigan, Ohio, western Pennsylvania and rural Maine.

Trende sees these people as "down-scale, blue-collar whites," many of whom live in rural counties and were part of the old Ross Perot coalition that denied a second term to President George H.W. Bush in 1992. Perot was an anti-Wall Street economic populist who strenuously opposed liberalization of immigration laws. It's conceivable that significant numbers of these voters have reversed their immigration views since 1992 and would now be more inclined to vote for a Republican who backed Schumer-Rubio. But none of the prospective 2016 GOP presidential aspirants are likely to bet their campaigns on such a dicey assumption.