WASHINGTON -- Republicans' search for a way back to presidential success is drawing a striking array of personalities and policy options, creating a wide-open self-reassessment of the party. GOP activists may need three full years to decide which candidate and which philosophy will serve them best in 2016.

Rival factions are trying to tug the party left or right, toward pragmatism or defiance, toward small-government purity versus pride in the good that government can do.

Traditional stands against gay marriage and against looser immigration laws are being challenged. And the tea party's influence - a mixed blessing in recent Senate races - looms large in early presidential jockeying after a muted role in the heart of last year's contest.

Sen. Rand Paul of Kentucky is generating nationwide attention with a libertarian-tinged message that drew modest attention until a short time ago.

Marco Rubio, a tea party hero since elbowing his way past Florida's Republican governor in the 2010 Senate race, is practically a GOP mainstreamer now. Republicans don't need a new idea, he told a recent gathering of the Conservative Political Action Conference, because they already have one. "The idea is called America, and it still works," Rubio said.

At the same conference, Paul espoused a different view. The Republican Party, he said, is "stale and moss-covered."

It's Paul - not Rubio or one of the several governors eyeing a presidential bid - who got the coveted invitation to headline the Iowa Republican Party's Lincoln Day Dinner in May.

It's possible, of course, that one Republican candidate will pull away from the pack over the next two years. But the absence of an early frontrunner is unusual for a party that traditionally picks its nominee with a next-in-line mindset, said Dan Schnur, a former Republican campaign aide who teaches political science at the University of Southern California. Now, he said, "there is no hierarchy."

Thus far, no one is creating more buzz than Paul, whose father, Ron Paul, is a libertarian champion and three-time presidential candidate. The younger Paul generally avoids his father's more esoteric issues, such as abolishing the Federal Reserve and returning to the gold standard.

Rand Paul's anti-war stand also is softer than his father's. But the junior senator from Kentucky gained widespread attention this month with a 13-hour filibuster challenging U.S. policy for using drones to kill terrorist suspects.

Soon thereafter, Paul won CPAC's presidential straw poll - as his father did in past years - and delivered a widely covered speech on immigration.

"Rand Paul is going to be a very serious candidate for president," said Steve Schmidt, a chief strategist for John McCain's 2008 presidential campaign. "He's going to challenge the orthodoxies, some of the litmus tests, of what has defined conservatism. The libertarian wing, which has been dormant, will assert itself."

Even Paul's occasional critics salute his fast rise.

"He's passionate, he knows no fear and he's true to his beliefs," said Sen. Lindsey Graham, R-S.C., who publicly rebuked Paul's remarks about drone policies.

"We're on different planets when it comes to foreign policy," Graham said. He cautioned Paul: "I think it's going to be difficult to lead the Republican Party without embracing peace through strength, the Ronald Reagan approach to national security."

The higher Paul soars, the more scrutiny his record will draw. That record might unsettle Republicans who say the party must edge toward the center to attract more voters.

Paul strongly opposes abortion, saying human life begins at conception and should be entitled to legal protection from then on. He muddied the waters in a recent CNN interview, however, saying "there are thousands of exceptions" that might make an abortion legal.

Paul also has struggled to explain changes to his once-firm stand against illegal immigration. In a major speech this month he set out a plan to let illegal immigrants remain in the U.S. and ultimately get a chance to become citizens, but he generally avoided direct references to citizenship.

Nearly equaling Paul in early presidential speculation is Rubio, 41, who is tasked with helping his party find better footing on immigration. Rubio, the son of Cuban immigrants, is trying to craft a lengthy but feasible path to citizenship for the nation's millions of illegal immigrants. Rubio and Paul may end up with similar positions, although Paul wants more stringent requirements for certifying that the Mexican border is secure before moving ahead with other immigration changes.

Hispanics voted overwhelmingly for President Barack Obama in 2008 and 2012. Some GOP strategists hope Rubio can reverse the trend.

Former Florida Gov. Jeb Bush, who has called for immigration reform and whose wife is Mexican-American, also is in the presidential mix. It's not clear whether he and Rubio can advance simultaneously. Also, Bush's father and brother left the White House with low approval ratings.

Rep. Paul Ryan of Wisconsin, the 2012 vice presidential nominee, is considering a presidential campaign that inevitably would draw scrutiny to his efforts to slash social spending without raising taxes on anyone, including the rich.

Warren G. Harding was the last Republican elected directly from the Senate or House to the presidency. As usual, several governors are weighing presidential bids. At least three - Chris Christie of New Jersey, Scott Walker of Wisconsin and Bob McDonnell of Virginia - might make a pragmatic, can-do argument, having governed toss-up or Democratic-leaning states.

But they already see the challenge of running in a party whose primaries are dominated by conservative activists.

Christie, who praised Obama's role in hurricane relief, was refused a speaking slot at CPAC. And conservative bloggers are hammering McDonnell for a Virginia transportation overhaul that includes new taxes.

Louisiana Gov. Bobby Jindal - a former Rhodes Scholar who urges Republicans to stop being "the stupid party" and obsessing over budgets - also might run for president.

Personalities aside, Republicans are bracing for an intense philosophical debate. Should they edge toward the political center to draw moderates and independents who helped elect Obama? And if so, how do they avoid antagonizing evangelicals, immigration hard-liners and other conservative stalwarts who comprise the party's base?

Schmidt notes that the base's loyalty didn't keep the party from losing the popular vote in five of the last six presidential elections.

If Republicans recalibrate their message "based on talk radio hosts and extreme bloggers, it's like putting a magnet to your compass," Schmidt said. "The readings go haywire," and there's no way to pick up the extra voters the party needs, he said.

Schnur, the consultant-turned-academic, said Republicans realize they can't win presidential races without changing. "A much harder decision is not whether to do things differently," he said, "but how."

• Read more articles by CHARLES BABINGTON

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