(CNN) – San Antonio Mayor Julian Castro, a Democrat, predicted Thursday Latinos will play an expanding role in the political future of Texas, a reliably red state.
"I think when you have that ground work and when you have the right candidates to excite folks, then you're going to start to see progress and within the next six to eight years, I believe that Texas will at least be a purple state, if not a blue state," Castro said on CNN's "Starting Point with Soledad O'Brien."
Castro, who gave the keynote address at the Democratic National Convention in September, argued the GOP's "tone on issues like immigration" and Republican positions against the 2010 health care law have turned Latinos away from the party. The new law, he says, will cover nine million more Latinos, which he called a "big deal" for a demographic that largely relies on the emergency room as "their primary care physician."
Latinos represent a growing portion of the national electorate, including 10% in this year's election, according to CNN exit polls. Of those who voted, President Barack Obama won 71% of their support, while Mitt Romney carried 27%. This year marked the first time the Latino electorate reached a double digit figure; in 2008, they represented nine percent of the vote.
Castro said in order to gain more support from Latinos, Republicans have to become a bigger tent party. "They can't tow the line of the tea party and expect they're going to be able to appeal to Latinos and other groups."
While that may be the case on a national level, Republican Sen. Kay Bailey Hutchison of Texas said the Lone Star State should be considered a model for the GOP in learning how to be more inclusive.
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