WASHINGTON » Fox News viewers in Florida will see a new commercial in the coming weeks urging them to call Sen. Marco Rubio. "Thank him for keeping his promise, and fighting to secure the border," a narrator says in the ad, which is paid for by the conservative American Action Network.

Another group, Americans for a Conservative Direction, led by former Gov. Haley Barbour of Mississippi and other top Republicans, has been running ads in Iowa lately that implore those watching to "Stand with Marco Rubio to end de facto amnesty."

And when the Americans for Prosperity Foundation, the Koch brothers’ political advocacy group, decided to move its signature annual conference outside Washington for the first time, it picked a spot right in Rubio’s political backyard: Orlando. The keynote speaker? Rubio.

Rubio’s advocacy for an immigration reform proposal that would allow those here illegally to gain a path to citizenship has made him a pariah among some rank-and-file Republicans.

But many of the most powerful and well-financed forces in the party are moving to provide cover for the Florida senator and Republicans like him who are pushing to overhaul the nation’s immigration system.

Their message: if we ever want to take back the White House, we have to stop devouring our own.

As the party assesses its chances for the 2016 presidential campaign, many Republican strategists believe that they need as robust a primary field as possible, with more than just one or two viable potential contenders.

A messy fight over a subject as touchy as illegal immigration is a prospect many Republican leaders are eager to avoid, especially since three of their best hopes for 2016 are closely tied to the debate: Rubio, former Gov. Jeb Bush of Florida, and Rep. Paul D. Ryan of Wisconsin, who is expected to play a vital role once the House starts debating the issue next week.

"I think we have a great bench," said Carlos Gutierrez, who was commerce secretary under President George W. Bush and leads the super PAC Republicans for Immigration Reform. "It’s whether we can stop becoming our own worst enemy."

Rubio is just one of several top Republicans who has taken a political risk by supporting the immigration reform plan that passed the Senate last week, but his situation is the most urgent. No public figure other than President Barack Obama is mentioned more often in news coverage of the immigration debate, an analysis by Kantar Media News Intelligence showed. His name appears in articles almost twice as often as Sen. Charles E. Schumer, who has often taken the lead in Senate negotiations.

His words have been turned into television commercials by groups on both sides of the issue. And no one has taken on more friendly fire. Rubio has been attacked at Tea Party rallies (his name elicits boos), on conservative radio ("a piece of garbage," Glenn Beck called him) and in National Review ("Rubio’s Folly" declared a recent cover).

Still, running interference on Rubio’s behalf is fraught with risk for conservative groups, who are going against many in their own base.

"We know that there’s a lot of folks on both sides," said Tim Phillips, president of Americans for Prosperity. "But I think the vast majority of people appreciate the fact that Senator Rubio is doing what he thinks is best for the country. And that he’s doing it in an open and honest way."

Phillips declined to discuss any implications for Rubio and 2016, but said, "We think that he’s got a bright future within the movement, and in whatever he chooses to do down the road."

Many other big players in the conservative movement would like to keep that future bright as well.

Ralph Reed, president of the Faith and Freedom Coalition, invited Rubio to speak to several hundred of his members at a conference in Washington last month. Reed, who has made clear that he believes the Senate immigration bill Rubio helped write is too lenient, described the crowd as right-leaning, by Republican standards. "Not the Chamber of Commerce variety," he noted wryly in an interview.

But when he introduced Rubio, he offered nothing but effusive praise. "We’re proud to count him as our friend because he has not forgotten who got him here," Reed told the crowd, which applauded politely. "He has not forgotten who he is."

Weighing heavily on conservative leaders is a reminder of how immigration policy bedeviled Mitt Romney last year. His "self-deport" comments about what should happen with the 11 million immigrants living illegally in the United States became an easy punch line for Democrats and helped drive Latinos even further away from the Republican Party.

And many see the success of an immigration reform package shaped with considerable input from Republicans like Rubio as key to their future, and his.

"Certainly the way in which the bill is perceived and Rubio’s own political fortunes are closely entwined," said Steven Law, president of American Crossroads, Karl Rove’s political outfit, which plans to play a larger role in the debate once House Republicans get deeper into their discussions.

"Our first priority is to promote and advance immigration reform, and to talk about the ways this advances conservative goals," Law added. "If we do that we will not only be helping to move legislation, but it will also protect those who stuck their necks out like Rubio."

Rubio, of course, is not the only beneficiary of such efforts. Republicans who backed the measure, including Sens. Lindsey Graham of South Carolina, who is up for re-election next year, and Kelly Ayotte of New Hampshire, another of the party’s rising stars, have attracted support.

The U.S. Chamber of Commerce, one of the most active and well-financed proponents of immigration reform, began a seven-figure nationwide ad campaign last week featuring Rubio, Ryan and Sen. Rand Paul of Kentucky, another 2016 contender.

And before its new Florida ad campaign, the American Action Network had already spent nearly three-quarters of a million dollars on pro-immigration reform commercials featuring Rubio and Gutierrez.

After Ayotte came out in support of the Senate bill and criticism from the right rained down on her, Republicans coordinated a response campaign that included a news conference hosted by four former Republican state party chairmen.

The men received a thank-you phone call from Rubio.

© 2013 The New York Times Company