(CNN) - Republican Sen. Rand Paul, who's become somewhat of a political celebrity after his nearly 13-hour filibuster last week, took the opportunity to critique his own party Thursday while speaking before a large crowd of conservatives.
"The GOP of old has grown stale and moss-covered," the Kentucky senator said at the Conservative Political Action Conference. "I don't think we need to name any names, do we? Our party is encumbered by an inconsistent approach to freedom. The new GOP will need to embrace liberty in both the economic and the personal sphere."
Paul is seriously thinking about a presidential bid in 2016, CNN Chief Congressional Correspondent Dana Bash reported last week. And entering the annual conservative gathering on Thursday, his camp was setting expectations high.
The first-term senator viewed the speech as an opportunity to establish himself as a mainstream Republican leader, a source familiar with his remarks told CNN White House Correspondent Brianna Keilar. Until now, his most ardent following has come from the libertarian wing of the GOP.
For the Republican Party to win, he said, "liberty needs to be the backbone of the GOP."
"We must have a message that is broad. Our vision must be broad. And that vision must be based on freedom," he added.
Paul also railed against the president for the government's increase in spending and debt in the last four years and ticked off examples of what he considered wasteful federal spending, including a grant that funded a study involving rattlesnakes and robotic squirrels.
Paul filibustered last week John Brennan nomination's to become CIA director, during which Paul gained a huge following online for his questioning of the Obama administration's drone program.
He demanded an answer from the administration over whether the president had the authority to order a drone strike against an American terror suspect on U.S. soil. Attorney General Eric Holder responded the following day, saying the answer is "no."
But Paul said his stand-off was about "much more."
"Do we have a Bill of Rights," he said. "Do we have a Constitution and will we defend it?"
– CNN's Kevin Liptak contributed to this report.