Washington (CNN) -- When presumptive Republican presidential nominee Mitt Romney appears before Latino small-business owners in Washington on Wednesday, he'll address a group whose explosive birth rates foreshadow a seismic political shift in GOP strongholds in the Deep South and Southwest. "The Republicans' problem is their voters are white, aging and dying off," said David Bositis, a senior research associate at the Joint Center for Political and Economic Studies, who studies minority political engagement. "There will come a time when they suffer catastrophic losses with the realization of the population changes." Over the next several generations, the wave of minority voters -- who, according to U.S. Census figures released this week, now represent more than half of the nation's population born in the past year -- will become more of a power base in places like Alabama, Mississippi and Georgia. That hold will extend across the Southwest all the way to California, experts say.
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Births of nonwhites have now overtaken births of whites, according to the U.S. Census
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Republicans face uphill battle in persuading Latinos to vote for their candidates
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Shift is most pronounced in the South and Southwest
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