Luke Sharrett for The New York Times

Ron Paul was Tea Party before Tea Party was cool.

A candidate of the fringe and the Libertarian college-age set in 2008, the 75-year-old representative from Texas announced his second run for the Republican nomination for president during an interview on ABC’s “Good Morning America” on Friday.

But if Mr. Paul remains the same, blunt-spoken, small-government rabble-rouser that he was four years ago, he and his top aides are betting that the times — and the Republican primary electorate — have changed in the interim.

“Time has come around to where the people are agreeing with much of what I’ve been saying for 30 years,” Mr. Paul said on ABC. “The time is right.”

The rise of the Tea Party movement offers Mr. Paul an opportunity to be embraced as a kind of mainstream candidate that he never was while running last time around.

Well, not mainstream, exactly. He still advocates the legalization of heroin, the elimination of half of the federal agencies and an immediate end to virtually all military “adventures” overseas. Plenty of Tea Party activists would say they are uncomfortable with many of those positions.

His path to the nomination, much less the Oval Office, is still difficult to imagine — perhaps even for Mr. Paul himself — given his apparent disregard for the niceties of political accommodation or any obvious effort to woo the party’s leaders.

And despite Mr. Paul’s remarkable ability to raise millions of dollars from his committed followers, it remains unclear whether he could raise tens of millions — if not hundreds of millions — from the nation’s wealthiest interests to compete with his Republican rivals and, ultimately, President Obama.

But there is no ignoring the sense that Mr. Paul’s timing may be spot on for the political times. And running for president gives him a national platform for the issues he has cared about for decades, as well as a chance to spotlight the new leaders of the movement, including his son, the new Republican senator from Kentucky, Rand Paul.

The new energy in the Republican party appears to come from the Tea Party activists whose primary issues are close to Mr. Paul’s: a rabid desire to cut government spending, a fear of the mounting national debt, a dislike of the politics of compromise and a distrust of the Republican establishment that goes almost as deep as their disgust with Democrats.

In fact, Mr. Paul claims to be the founding father of the movement.

“Of course, the Tea Party movement was started during the last campaign when there was a special day where they raised $6 million spontaneously,” Mr. Paul said during a debate among potential Republican candidates last week in South Carolina. “And that was the beginning of it.”

The reference was to Dec. 17, 2007, when supporters of Mr. Paul’s raised more than $6 million for his presidential candidacy on the anniversary of the Boston Tea Party. Issues of spending, taxes, debt and freedom helped fuel the fund-raising “moneybomb” that kept Mr. Paul in the 2008 race well into June.

But even that infusion of cash didn’t make Mr. Paul a real contender in 2008. With no real campaign infrastructure and a reputation as a fringe candidate, Mr. Paul did not win a single state during the primary process.

And while he entered the Republican convention with close to three dozen delegates (he came in second place in a dozen or so states), Mr. Paul was never taken seriously by those running the convention on behalf of the party’s nominee, Senator John McCain of Arizona.

In 2012, Mr. Paul enters a presidential race that is, if anything, even more unsettled than the 2008 Republican campaign was at the same point in time.

His supporters say he is poised to make a more serious run at the nomination. Drew Ivers, a member of the central committee of Iowa’s Republican Party, is a committed supporter of Mr. Paul’s.

“The spending. The war. The financial crisis,” Mr. Ivers said recently. “That’s how snowballs develop, you know. They start small, and they get bigger as they roll downhill.”

And while it may seem unlikely that the Republican Party would choose an irascible man in his mid-seventies to be their standard bearer, Mr. Paul tends to shrug off all the second-guessing with an affable humility.

Asked at the debate whether he was suggesting that heroin and prostitution are an “exercise of liberty,” Mr. Paul thought for a moment — clearly recognizing the political trap — and then barreled ahead.

“You put those words someplace. But yes, in essence, if I leave it to the states, it’s going to be up to the states,” Mr. Paul said. “Up until this past century, you know, for over 100 years, they were legal.”

He went on, clearly enjoying himself: “What you’re inferring is, you know what, if we legalized heroin tomorrow, everyone is going to use heroin. How many people here would use heroin if it were legal? I bet nobody would put the hand up, ‘Oh, yeah, I need the government to take care of me, I don’t want to use heroin so I need these laws.’ ”

The sarcasm was evident, and the transcript of the debate accurately captures what happened next: Cheers, applause.