Mitt Romney earned only 23 percent of the Latino vote — less than John McCain, who won less of the Latino vote than George W. Bush. If Republicans don’t reverse this trend with America’s fastest-growing demographic, they won’t just have difficulty winning the presidency, they could lose Texas and cease to be a national party.

The GOP seems to have a two-prong plan to win over Latinos — pass immigration reform and make Senator Marco Rubio (R-FL) the face of the GOP.

Rubio has made himself a key player in reform, taking it upon himself to sell the idea to conservatives and trying to build certain measures into that law that make the path to citizenship arduous and punitive. But he’s also — as Talking Points Memo‘s Benjy Sarlin describes  —  kept “one finger on the eject button.”

On Sunday, as the so-called “Gang of Eight” in the Senate was celebrating a tentative agreement on all major components of the law, Rubio released a statement designed to be a rain cloud over a parade.

“I’m encouraged by reports of an agreement between business groups and unions on the issue of guest workers,” Rubio said. “However, reports that the bipartisan group of eight senators have agreed on a legislative proposal are premature.”

Why would Rubio want to dabble so heavily in selling reform and then constantly threaten to sabotage it?

The junior senator from Florida knows that his party needs these reforms. The failed effort at similar legislation in 2007 cost the party and doomed the presidential candidacy of John McCain. For this reason alone, he has to be seen putting in a serious effort.

“In the end, Rubio has to be able to say to conservatives something along these lines: ‘I fought with Democrats. I told them what we needed to allow undocumented workers a path to citizenship. They didn’t want it but I held firm and we got it done.'” writes The Washington Post’s Chris Cillizza.

If Rubio doesn’t support the final bill, it has almost no chance of passing the House.

Make no mistake: Rubio is the diff b/w the Senate legislation getting 75 votes vs. 60 — and 75 votes is impt to pressure Boehner/House GOP

— Mark Murray (@mmurraypolitics) April 1, 2013

But here’s the rub for the GOP: If reform fails, if Rubio says “Obama just went too far left for me” to keep up with Ted Cruz (R-TX) — who has already said he’s against any path to citizenship — it hurts the party in 2014 and 2016, but it also makes the Cuban-born Rubio even more essential to the GOP, suggested Time magazine’s Mike Grunwald — who wrote a cover-story profile on Rubio called “The Republican Savior” — in a Twitter conversation over the weekend.

Republicans need to find a way to get at least 30 percent of the Latino vote. Rubio captured 55 percent of Florida’s Latino vote in 2010. Though the state is home to far more Cubans than the rest of the nation, it’s still an impressive number.

Currently a path to citizenship is supported by 49 percent of the community while 48 percent support Obamacare.

If Republicans can’t lure them with policy, their only hope is personality. So basically whether immigration reform passes or not, Rubio is their only hope. That gives him plenty of room if he decides that whole thing is going down and he wants to eject.

Photo: Gage Skidmore via Flickr.com