You can question Hillary Clinton's political scruples. But don't doubt her political smarts.

There is no better proof of either quality than her U-turn decision last week to go all out in embracing amnesty for undocumented immigrants. Clinton's gambit is a major flip-flop—one that will put Republicans in a bind that they'll have a hard time extricating themselves from. It's heads she wins and tails they lose, regardless of what they do.

Clinton stunned everyone—even Latino activists—when she boldly called for a "path to full and equal citizenship" for all of the roughly 12 million illegal immigrants in the country. Speaking at a gathering of handpicked young immigrants in a high school in Nevada, a Latino-heavy swing state, she rejected the notion of a mere path to legalization—like the sort Jeb Bush and some of the more immigrant-friendly Republicans have skittishly backed. "That's code for second-class status," Clinton declared. She promised to go much further than even President Obama's recent executive action and "defer" deportation proceedings not only against some illegal immigrants, but virtually all of them, while working toward comprehensive immigration reform that included citizenship.

This was a remarkable shift for someone who has not only maintained a studious silence for months about Obama's executive action, but also previously opposed drivers licenses for illegal immigrants. Indeed, her flip is so dramatic that instead of raising questions about her credibility, it has changed the conversation so much that we're immediately asking what Republicans need to do to catch up.

No doubt her proposal, which she offered no realistic plan for pushing through an unfriendly Congress, is designed to deflect attention from "Emailgate" and any number of other scandals that might yet derail her candidacy. But that's not all its aimed at doing.

Its chief purpose is to compound what pollster Whit Ayres calls the GOP's "daunting demographic challenge" in 2016.

Ayers points out that Mitt Romney got 59 percent of the white vote in 2012, the highest percentage of any Republican challenging an incumbent president, and still lost because he got only 18 percent of the overall minority vote and 27 percent of the Latino vote. However, the white share of the national electorate is on track to drop by three percentage points (from 72 percent in 2012 to 69 percent in 2016)—and the minority share, likewise, to rise by the same amount.

This means that the GOP candidate has to do one of two things to win against Clinton: Improve his or her performance with whites to about 65 percent, a feat only Ronald Reagan has accomplished in the last 50 years, or boost his or her minority vote to 30 percent, which would require drawing about 45 percent of the Latino vote—as George W. Bush did.

But here's the thing: While Democrats' white and minority supporters are united on the issue of immigration (or at least not hopelessly divided), the GOP's are not. This means that the more Republicans question and condemn Clinton's support for "amnesty," the more they'll dig themselves in a hole with Latinos and make her more popular. On the other hand, it they stay mute—which is what most of them have done (with the exception of Lindsey Graham)—they'll risk alienating the anti-amnesty white base that they have spent the last decade riling up.

In other words, if Republicans fight Hillary's call for amnesty, they'll lose Latinos, which will benefit Hillary. But if they don't, they'll lose whites, which will also benefit Hillary.

The dilemma is particularly acute for Jeb Bush, whose broad support for immigration (along with his Mexican-American wife and Spanish fluency) has made him perhaps the best-placed Republican to do well among Latinos. Yet even he doesn't come anywhere close to the 45 percent mark yet. He has been rather equivocal in his support for a path to citizenship and has been assuring GOP voters that whatever course he charts for the undocumented, it will require them to jump through all kinds of hoops, such as paying fines and passing English tests and possibly "touching back" to their home country. Still, a recent Bloomberg poll found that 41 percent of likely Republican voters in New Hampshire, far from the most restrictionist state in the country, considered his immigration views a "deal-killer."

By positioning herself as even more pro-immigration than the most pro-immigration GOP candidate—and potentially picking as her running mate Julian Castro, secretary of Housing and Urban Development and the former mayor of San Antonio who is wildly popular with Latinos—she will basically lock up the Latino vote. This will mean that the Republican nominee, even Jeb Bush, would have to go whole-hog for the white vote by hardening his or her opposition to amnesty and immigration, further cementing the GOP's reputation as the anti-minority, white man's party.

Some pundits pooh-pooh this problem, noting that like all voters, Latinos list jobs and the economy as their top concerns, not immigration. That's true. But, also like all voters, Latinos won't put their economic faith in someone they don't trust politically. They will have much more confidence in Clinton solving those problems, not because they necessarily buy into her liberal tax-and-spend plans, but because they have more confidence in her personally, thanks to her appeal for them on immigration issues.

What's more, life will get only more miserable for Republicans once Clinton enters the White House and makes comprehensive immigration reform her signature issue. That's because if Republicans go along with her plans to extend full-fledged amnesty, they will basically be handing her a whole new block of Democratic voters. But if they don't, Democrats will be able to milk this issue in subsequent elections, when the electorate is even more Latino.

Regardless of where one stands on the merits of the issue, the political reality is this: Republicans' harsh anti-immigration rhetoric has left them no good options. They have created their own vulnerability. And Hillary Clinton has just zeroed in on it.

This column originally appeared in The Week