In the ongoing argument over how the Republican Party can move forward after losing last year's elections, Florida Senator Marco Rubio has had a clear, coherent perspective. The GOP doesn't need to change its policies—it just needs to reach out to key voters, like Latinos, and bring them into the tent. To do that, Republicans need to appeal to the immigrant identity, and present the Democratic Party as a throwback to "the countries that your parents and grandparents came here to get away from."

But there's a roadblock. As he put it during a January address to the conservative Hispanic Leadership Network, "It’s a difficult message to get to because the gateway issue of immigration stands in the minds of so many people who we live next to and love."

In other words, the party's stance on immigration keeps it from building common cause with voters who, as Rubio has described them, have a native social conservatism and enthusiasm for entrepreneurship.

And so, his solution—shared by many other Republicans—is to remove the barrier and get behind comprehensive immigration reform. Which is what he's done this week with the bill unveiled by the Senate's "Gang of Eight." "I think part of my job is to explain to people what it is we’ve worked on," said Rubio on CNN this past Sunday "try to justify it and hopefully gain their support … I hope I can convince people that this is the right approach."

But Rubio has a problem. The foundation of his pitch—that immigration is the issue separating Latinos from the Republican Party—is shaky. You can see the rationale: George W. Bush's "compassionate conservatism" included a real interest in unauthorized Latino immigrants that yielded him more than 40 percent of the Hispanic vote in 2004. And while John McCain lost in the following election, his long-standing relationship with Latino voters (by way of representing Arizona) earned him 31 percent support from Hispanics.

Mitt Romney, by contrast, ran to the right on immigration, hailing "self-deportation" and endorsing draconian laws like the ones in Alabama, Georgia, and South Carolina. His total? 27 percent support from Latino voters, a low point for a Republican presidential candidate since at least 1972.

It stands to reason that Republicans can improve their standing if they adopt the approach of Bush, McCain, and other Southwestern Republicans, like Texas Governor Rick Perry. Unfortunately, it's not that easy.

First, there's the simple fact that Latinos lean further to the left than most Americans. The numbers speak for themselves. Seventy-five percent of Hispanics say they support bigger government with more services, and 30 percent describe themselves as "liberal," compared to 21 percent of the general population. They're highly supportive of Obamacare, and broadly in favor of gay rights.

If there's any place for Republicans to make inroads, it's abortion—51 percent of Latinos say it should be illegal in all or most cases. But even then, it's not clear abortion is a marquee issue for the group in the way that it is for white evangelicals.

To this wall, you should also add the Democratic Party's long relationship with Hispanics. Remember, Barack Obama wasn't the first Democrat to secure a large advantage among Latinos. Jimmy Carter won 56 percent even as he suffered a landslide loss to Ronald Reagan, and Michael Dukakis repeated the feat, winning 70 percent of Latino voters while losing the country to George H.W. Bush. On average, in the seven presidential elections before 2008, Democratic candidates finished with more than 60 percent support from Hispanic voters. Obama overperformed the average, but not by much.

Republicans can lead on immigration reform, and they might improve their image with some Latino voters. It will take more than that, however, to reclaim lost ground.

But even if Republicans were to make up lost ground among Latino voters by passing immigration reform, it wouldn’t do much to change the electoral map in 2016 and beyond.

Mitt Romney would have had to have won two thirds of Hispanic voters in order to close the popular vote gap without additional votes from other groups. There's nothing Republicans could do in the near future to shift Latino voters by that magnitude–and even if they did, there's still the Electoral College to consider. Most Latino voters live in states that aren't especially competitive: Arizona, New Mexico, Texas, and California. In the states that determined the election, there are relatively few. In Ohio and Virginia in particular, Romney would have had to have won the overwhelming majority of Hispanic voters to overtake the president.

The country needs sensible immigration reform, and for that reason, we should applaud Republican efforts to clear the path forward. But the GOP is kidding itself if it thinks it can make gains with a single gesture.

All that said, there is a bright side for Republicans to consider: it's not unusual for a political party to lose the White House for eight years. You could even call it the norm. And afterward, the pendulum almost always swings back to the party that was out of power. Republicans could win 2014 and 2016 without changing a single thing about their party or their approach. In which case, immigration reform is nice, but not necessary.