Even after, thanks to Fox News, the first 2012 Republican presidential candidates debate in Greenville, S.C., no semi-serious person can pretend that (s)he knows whom the Tampa GOP Convention will nominate in late August of next year to challenge President Barack Obama. But I am confident enough about one Republican prediction about 2012 to wager a cold drink of your choosing.

First, understand that Republicans have historically been quite orderly and expected about this presidential nominating responsibility. In 14 of the last 15 presidential elections, the Republican presidential candidate who led in the Gallup Poll conducted closest to one year before the nominating convention went on to win the nomination.

The only exception was in the last race, when in the September 2007 Gallup survey, former New York Mayor Rudy Giuliani held a substantial lead, while the eventual standard-bearer, Sen. John McCain, was running third behind former Tennessee Senator and star of screen and TV Fred Thompson.

Democrats are both unforeseeable and whimsical in picking their presidential candidate. Consider that, one year before each man was chosen, Democratic White House nominees George McGovern, Jimmy Carter, Michael Dukakis and Bill Clinton were all favored by fewer than 5 percent of the voters in the Gallup Poll. Just one year before he won the 2008 Democratic nomination, underdog Barack Obama trailed then-Sen. Hillary Clinton by more 20 points.

Which brings me to my take-it-to-the-bank Republican prediction for 2012. While I have no idea who will capture the GOP prize, I'm beyond confident that the 2012 nominee will ask the junior U.S. senator from Florida, Marco Rubio, to become her/his vice-presidential running-mate.

Think about it: Marco Rubio, the son of Cuban-born parents who worked in hotels — his father as a bartender, his mother as a housekeeper — will be a youthful 41-year-old and, more importantly for his party, the only Hispanic Republican in the Senate.

In 2008, John McCain, despite a long record of support for immigrant rights, was punished by Hispanic voters for the immigrant-bashing from so many Republicans. In 2004, George W. Bush had won 44 percent of the Latino vote against Democrat John Kerry. But in 2008, 67 percent of Latino voters backed Obama, while McCain got just 31 percent.

This has happened while the Latino population in the U.S. has grown in the last decade to more than 16 percent of the total, becoming the country's largest minority group. Almost one-quarter of the U.S. population under the age of 17 is Latino.

While the U.S. is becoming more racially diverse (Obama won 80 percent of the 27 percent of the electorate that is Asian-African American-Latino-and other), Republicans have become an increasingly more white party in an increasingly less white nation.

In his 2010 winning Senate race, Rubio — against Democrat Kendrick Meek and Republican-turned-independent Gov. Charlie Crist — won 55 percent of the Latino vote in Florida. Florida, it should be noted, picked up two more House seats as a result of the most recent census and will in the 2012 presidential election have 29 electoral votes — the same number as New York.

With an authentic log-cabin background along with considerable personal appeal and real political skills, Rubio is the logical running-mate for almost any Republican next year.

True, he is on the record as saying he is not at all interested in the VP slot. But the vice presidential nomination, as Bill Vaughn wisely observed, is "a lot like the last cookie on the plate: Everybody insists he won't take it, but somebody always does." If the Republicans are shrewd in 2012, that somebody could be Marco Rubio.

To find out more about Mark Shields and read his past columns, visit the Creators Syndicate web page at www.creators.com.