By: Gwen Ifill

Christine Mastin, an immigration attorney whose Spanish-speaking grandmother emigrated from Chile to the United States, realizes that most of the Hispanics she knows are surprised she is a Republican.

Barack Obama won two-thirds of the Latino vote in 2008, and no Republican has come close to winning a majority in 40 years. But she is working Colorado for Mitt Romney.

And even though she ran for a state House seat in 2010 and lost, she is optimistic that the GOP will soon be able to crack the code.

"Maybe it might strike folks a little odd that I would be a Republican," she told me recently. "But the Republicans truly believe in individual liberty, hard work, entrepreneurialism, allowing families to build themselves up and really succeed in this country. And all of those values are aligned not only with America generally, but also the Latino community."

This is a pitch Republicans hope will reverse a growing demographic dilemma. U.S. Census figures now estimate that more children of color are being born than Caucasians. This is not good news for a party that has been largely dependent on white voters.

Many Republicans know how these numbers work. President George W. Bush spoke expansively about big tents and the value of (legal) immigration. At a campaign appearance recently in South Florida, Mitt Romney conceded that failing to win more of the Hispanic vote would spell "doom" for the GOP. But when he arrived in Washington this week to speak to a Latino business group, he sailed through his speech with not one mention of the demographic dilemma.

How much of a dilemma? Check out this graphic from The Washington Post. One chart shows the rate at which Hispanics have voted for Republicans (sluggish) while the other shows the rate at which the Hispanic population is growing (robust).

"When Bill Clinton was elected president of the United States, about 3.7 percent of the electorate was Latino," Stanford political scientist Gary Segura told me. "In this election year it will be just under 10 percent. So the votes more or less tripled. And when you have that many more people and that many more voters they matter in more places."

Segura calls it "demographic panic."

Moreover, Segura points out that the story no longer begins and ends in Florida, Texas and California. "We are surprised to hear that Latinos count in places like Wisconsin," he said, "or Pennsylvania or Virginia -- places that we don't think of as Latino-intensive states but where there's a growing Latino population and a growing Latino electorate."

It is no accident that those are also 2012 battleground states. That's why I went to Colorado to try to tell the story this year. You'll see what I discovered on an upcoming PBS NewsHour broadcast. But suffice to say, the GOP's uphill battle is clear.

Ryan Call, the Colorado Republican Party chairman who learned to speak Spanish as a Mormon missionary, says his goal is to convince Hispanic voters that Barack Obama has failed them.

"The price of gas doubled under Barack Obama's administration," he said. "Those are the issues that are really hitting the Hispanic community the hardest. And those are issues that the president has really failed on. So for us as Republicans, how are we going to appeal to this Hispanic community? It's talking about those issues and outlining with great clarity and principle how we're going to help create opportunities for their businesses to succeed, jobs to be had, opportunities for higher education, those are the things that are the most important to our Hispanic neighbors."

It may be a tougher sell to convince Hispanics that Republicans support their views on illegal immigration, which concentrate on law enforcement and shrinking the pathway to citizenship

While polls show that most Hispanics do not cite immigration as their chief concern, Democrats and some worried Republicans acknowledge it is an emotional, gateway issue for first- or second-generation Latino-Americans who might otherwise be persuaded to consider voting for a Republican.

"The rhetoric that came out of the primary campaign in the Republican Party was so negative to Latinos generally that even Latinos who were not that supportive of immigration reform were offended," former Denver Mayor Federico Pena, a Democrat, told me. "So Republicans have an uphill climb here, but we have the challenge of making sure that the excitement level, the motivation, the enthusiasm is there not only among Latinos but among all Democrats."

There's the rub. Enthusiasm appears to be an elusive commodity this election year. Between now and the fall, an old formula will have to fall into place - each party will have to do its best to excite its base and depress the opposition. A lot of that activity will happen in Hispanic communities.

Gwen's Take is cross-posted with the website of Washington Week, which airs Friday night on many PBS stations. Check your local listings.