WASHINGTON (AP) -- Of the handful of tea party-backed Republicans eyeing a 2016 presidential bid, Sen. Rand Paul is emerging as the most forceful in pushing libertarian principles, especially on anti-terrorism issues.
Rather than playing it politically safe, the Kentucky freshman is attacking government surveillance programs that many other Republicans - and many American voters in general - defend.
It could hurt him if GOP activists, who dominate primary elections, decide Paul over-emphasizes privacy at the expense of secret data-collection programs, which the administration says are essential to detecting potential terrorists.
The strategy suggests Paul hopes to inherit his father's libertarian loyalists even if it might complicate efforts to reach a much wider electorate, capable of nominating him - and electing him - to the White House.
Ron Paul was never a strong contender for the GOP nomination. Many people dismissed him as a fringe candidate with nonmainstream ideas, such as returning to the gold standard and ending the "war on drugs."
His son can't afford that label if he hopes to go further politically.
At a Washington news conference Thursday, Rand Paul urged Americans to sign a petition supporting an eventual class-action lawsuit. It will contend that the surveillance programs violate constitutional protections against unreasonable searches and seizures, he said.
"Americans are rightly concerned about having all of their phone records collected and monitored all of the time," Paul said. Joining him were several tea party-leaning House members and officials from the American Civil Liberties Union and other groups.
The on-line petition also seeks donations to Paul's political action committee.
Recent news reports described two far-reaching programs run by the National Security Agency. One gathers hundreds of millions of U.S. phone records to search for possible links to terrorists abroad. The other lets the government tap into nine U.S. Internet companies and gather all communications to detect suspicious behavior that begins overseas.
The NSA's director, Army Gen. Keith Alexander, told Congress the programs have helped thwart dozens of terrorist acts.
Paul's activism contrasts with more cautious reactions by other possible 2016 presidential contenders, including some with strong tea party support.
Sen. Marco Rubio, R-Fla., largely defends the surveillance programs. "We're trying to stop really bad people from doing really bad things," he told reporters this week.
"These programs are effective in that regard," Rubio said. "But if they are not properly managed, you can foresee how they could be abused."
Another tea party-backed senator weighing a presidential run - Ted Cruz of Texas - said of the surveillance programs, "What we have seen so far is troubling." However, Cruz said, "at this point we don't have a clear picture of what their policy is."
Some GOP leaders, including House Speaker John Boehner, forcefully defend the surveillance programs.
Depending on how they're worded, polls show varying degrees of public support for the NSA techniques. A Gallup poll - it described government collection of phone and Internet records as part of "efforts to investigate terrorism" - found most Americans disapproved.
Disapproval was strongest among Republicans, a sentiment that Paul might wisely be tapping, analysts said.
Paul "has his finger on the pulse of conservatives," said veteran GOP strategist Terry Holt. However, he said, it's too early to determine how the surveillance issue will play out in Republican primaries three years from now.
Kyle Downey, who worked for Mitt Romney's 2012 presidential campaign, agreed. The privacy rights issue "has potential to become a populist front," Downey said. "Paul could use an issue like this to rally support with both his and his father's fundraising network."
Paul said he hopes millions of Americans will join a class-action lawsuit challenging the NSA programs. "There is a large groundswell of people who are upset about their privacy," he said.
If true, it may help Paul's legal ambitions this year. And it may fuel his political ambitions in 2016.
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