It's no secret: Texas is big. And it's getting bigger.

The Lone Star State has added about 5 million people since the turn of the century, and its population is expected to swell by another 5 million by 2020.

This week, NPR examines the dramatic demographic shifts underway in the Lone Star State in our series Texas 2020. We'll look ahead to how the second-biggest state could change in the next decade — and what that could mean for the rest of America.

In the first decade of this century, the population of Texas grew more than twice as fast as the rest of the country.

Former state demographer Steve Murdock says that's nothing new.

"Texas has always been a rapidly growing state," says Murdock, now a professor at Rice University in Houston. "In fact, in every decade since Texas became part of the U.S., it has grown more rapidly than the country."

What is new, Murdock says, is how Texas is growing: Two-thirds of the increase comes from Hispanics, while the population of non-Hispanic whites — the group Texans call "Anglos" — is barely growing at all. Anglos are no longer the majority in Texas, and Hispanics are expected to outnumber Anglos within about a decade.

"The face of Texas is changing from one where non-Hispanic whites were dominant in numbers to one where we're an increasingly diverse population, a multiracial and ethnic population, with lots of dimensions of that," Murdock says.

Political Effects

One of those dimensions is political. Democrats haven't won a statewide election in Texas in almost two decades. But if they could capture a large share of that fast-growing Hispanic population — as they have elsewhere — they would be a lot more competitive.

Steve Munisteri, the chairman of the Texas Republican Party, is on the lookout for that. A few years ago, he started going to Republican National Committee meetings toting a slideshow about changing demographics — and a simple warning for his fellow GOP leaders: "The Republican Party could never win a national election again unless it did a more effective job at reaching more diverse communities."

"Frankly," he says, "that wasn't paid much attention to at that time, but then when we lost 80 percent of the traditional minority vote in November, I got asked to re-give the same presentation I'd made a couple years earlier. So I think the RNC gets it now, but they certainly should look to Texas as to how to do it."

The Turnout Challenge

Munisteri notes that Texas Republicans like Gov. Rick Perry and former President George W. Bush generally fare better with Hispanic voters than Republican candidates elsewhere.

"We recognize the importance of the Hispanic community in our state," Munisteri says. "This idea that the Hispanic voters in Texas overwhelmingly vote Democratic is simply not accurate."

What is accurate is that most Hispanics in Texas don't vote at all. Last year, turnout among eligible Hispanic voters in the state was just 39 percent — nearly 10 points below the Hispanic turnout nationally, and even further behind the turnout in battleground states like Colorado, Florida and Virginia.

Ruy Teixeira of the left-leaning Center for American Progress says that leaves a lot of upside potential for Texas Democrats if they can turn out more of the Hispanic vote.

"Every year, the share of Hispanic voters in Texas goes up," he says. "If you were able to fully take advantage of that increase, it would actually go some significant way toward turning Texas, if not blue, at least purple."

California Transplants

One factor working against that, though, is the Anglo vote in Texas, which remains overwhelmingly Republican. That's one reason that Texas looks so different from other states with big Hispanic populations, like California.

Over the last decade, though, hundreds of thousands of liberal, white Californians pulled up stakes and moved to Texas — a reversal of the old Dust Bowl migration in the 1930s.

"A lot of these people will be importing new views, viewpoints, values into the state of Texas, and it's probably going to moderate that state's Republican-leaning and conservative traditions," says political scientist James Gimpel of the University of Maryland.

Gimpel has been studying those California transplants. They are not, for the most part, political pilgrims. Just people looking for work. But as newcomers leave the Democratic cities of California to settle in Houston, Dallas and Austin, Gimpel says they are helping to tip the balance in Texas towards that state's urban, Democratic enclaves.

"I don't think you can bring in this many people from these predominantly Democratic areas and Democratic states without it eventually changing your politics," he says.

Munisteri, the GOP chairman, insists he's not worried about the Democrats eyeing Texas hungrily, like a big enchilada. He likens the upcoming contest to a Friday night football game.

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