OXON HILL, Maryland (Reuters) - The Republican Party heard contrasting messages on Thursday about how to recover from last year's election defeats as two possible contenders for the next presidential campaign in 2016 brandished their conservative credentials.
Addressing a high-profile conference of party activists, Florida Senator Marco Rubio laid out a traditional social conservative agenda and criticized same-sex marriage.
Senator Rand Paul urged Republicans to embrace libertarianism and warned that the "moss-covered" party was turning off young voters who want to decriminalize marijuana.
Son of three-time White House candidate Ron Paul, the Kentucky senator is seen by old-guard Republicans like Senator John McCain as an unstable nonconformist on domestic issues and too isolationist on foreign policy.
Fiscal conservative Rubio is closer to the Republican establishment, which is eager to flaunt his Hispanic credentials to help win back Latino voters who overwhelmingly picked President Barack Obama over Republican Mitt Romney in November's election.
Rubio threw red meat to the Conservative Political Action Conference held just south of Washington, an annual gathering where the party often sizes up early presidential hopefuls.
"Just because I believe that states should have the right to define marriage in the traditional way does not make me a bigot. Just because we believe that life - all life, all human life - is worthy of protection at every stage of its development does not make you a chauvinist," the 41-year-old Cuban-American said.
Perhaps concerned about adverse reaction from conservatives, Rubio did not highlight the issue with which he is most associated in Washington: immigration reform.
The Florida lawmaker is one of eight senators from both parties who are working on legislation that could eventually give the 11 million illegal immigrants in the country a path to citizenship, something opposed by many on the right wing of the Republican Party.
In his speech, Rubio said the families were under threat from same-sex marriage and jokingly described liberals are "freeloaders."
"Do not underestimate, I know this movement does not, the impact that the breakdown of the American family is having on our people and our long-term future," Rubio said.
'STALE AND MOSS-COVERED' PARTY
Speaking directly after his Senate colleague, Paul took a swipe at older Republicans.
"The GOP of old has grown stale and moss-covered. I don't think we need to name any names, do we? Our party is encumbered by an inconsistent approach to freedom," Paul said.
That may have been a jab at McCain, who called Paul, 50, a "wacko bird" for talking almost 13 hours nonstop in the Senate last week. McCain, 76, lost to Obama in the 2008 presidential election.
Paul was using a procedure known as a filibuster to disrupt the confirmation process for Obama's new CIA director, John Brennan, and raise questions about the administration's ground rules for using drones in the United States.
In the kind of comment that won large youth support for his father during last year's presidential campaign, Paul told Republicans on Thursday not to lose the young.
"Ask the Facebook generation whether we should put a kid in jail for a non-violent crime of drug use and you'll hear a resounding, 'No,'" he said. "Ask the Facebook generation if they want to bail out too-big-to-fail banks with their tax dollars and you'll hear a 'Hell, no.'"
Judging by the popularity of bright red T-shirts and stickers bearing his name, Paul won the affection of young activists who turn the three-day event into a conservative spring break.
They have taken "Stand with Rand" as their mantra, following his filibuster last week. Many chose to stand throughout Paul's 19-minute speech on Thursday.
"I'm a longtime supporter of Ron Paul, and Rand Paul is a continuation of a movement that Ron Paul started," said Aaron Rainwater, 23, of Arlington, Virginia.
The senior Paul's presidential runs failed to win over mainstream Republicans, something the younger Paul's supporters believe the freshman senator is capable of doing.
"He's his father's son in the best sense possible, but not his father's son in the best political sense," Rainwater said.
LOOKING TOWARD 2016
It is more than 1,300 days until voters cast their ballots for the next president, but the thousands who traveled to the CPAC conference were already casting their mind toward 2016.
"We are defined by how quickly we pull ourselves off the mat," former Florida Representative Allen West told the audience.
In its 40th year, the conference, like the party it is trying to re-energize, is currently an ideological muddle.
In non-election years, attendees have shown a bent for backing the likes of Ron Paul and evangelical leader Gary Bauer in its annual straw poll. The result of this year's poll will be announced on Saturday.
Outside Washington, a handful of governors have also captured the affection of party activists.
Among them are Bobby Jindal of Louisiana and Scott Walker of Wisconsin, who are both attending CPAC this week and have raised their profiles by distinguishing between carrying out conservative reforms in their states and the gridlock in Washington.
Some senior Republicans are noticeable by their absence from this year's conference, organized by the American Conservative Union.
New Jersey's Chris Christie, a Republican governor in a Democratic-dominated state, was not invited despite having one of the highest approval ratings in the country.
Christie upset some Republicans by praising Obama's handling of the disastrous effects of Superstorm Sandy, which slammed New York and New Jersey just days before the election.
Virginia Governor Bob McDonnell will also not attend this year. He ruffled Republicans' feathers by signing a transportation bill that included a tax hike.
Conservatives looking to put the Romney campaign behind them have one obstacle this week: Romney himself, who is scheduled to address the CPAC audience on Saturday.