— It’s never too early to start thinking about 2016.

As Rep. Ron Paul, the oldest candidate in the Republican field, heads into what could be his final Iowa caucuses, his motley band of supporters is buzzing about a second coming — Sen. Rand Paul.

Rand Paul, 48, rode the wave of voter discontent in 2010, winning a U.S. Senate seat in Kentucky and promptly claiming the title of tea party senator. Ron Paul, 76, campaigned for his son, and his son is returning the favor.

At five well-attended whistle-stop rallies across the state, Paul the younger joined Paul the elder, showing that the septuagenarian congressman not only has been able to expand his support but also has the capacity to extend his brand.

While it’s not uncommon for the children of presidential candidates to stump for their parents, there is perhaps no more effective surrogate than Sen. Paul, who has voted in lock step with his father on issues that are key to fiscal conservatives and who is proof to tea party voters that the movement has moved to Washington.

The Paul camp, hoping for at least a third-place finish in Iowa, has deployed the senator to tout his father’s anti-establishment credentials.

“Anybody here want their government to mind their own business?” Rand Paul asked, garnering a raucous “yes” from the audience, before introducing his dad in the ballroom of a downtown Marriott. “There is only one candidate who will balance the budget in one term . . . there is only one candidate who has never been accused of flip-flopping . . . that candidate is my father.”

While Sen. Paul is an ideological copy of his father and they both have medical degrees, their onstage presence couldn’t be more different.

Where his father can be professorial, going from one run-on sentence to the next, name-dropping Austrian economists along the way, the senator from Kentucky is succinct, more down-home (the Southern drawl helps) and less cranky.

And people have noticed.

Supporters say Rand Paul is a good speaker, a compliment few bestow on his father.

“People who are very interested in liberty have been following the career of Rand Paul just as closely as they have been following Ron Paul. He is very well respected; I see really good things for him in the future,” said Kim Pearson, an Iowa state representative who will caucus for Paul on Tuesday. “Some people have told me that they have reservations about Ron Paul because when he speaks, he sometimes skips steps one through ten. But they don’t have reservations about Rand Paul, who his father says does a really good job delivering the message.”

The fervent followers, who show up at Paul rallies clutching his books and chanting “end the Fed,” see in the Kentucky senator the next torch-bearer for the Paul doctrine.

“Rand Paul is a chip off the old block. He stands for the same things Ron Paul stands for, and I support him,” said David Kaniuk, 31, of Pleasant Hill. “He is positioned well to pick up his father’s legacy. It just depends on if he wants to.”

The father’s legacy includes a yawning ground game here and in 10 other states including Nevada, Colorado and Washington, a savvy fundraising infrastructure and a legion of supporters who speak about Rep. Paul in messianic ways.

“To me, he’s my Noah,” said Sharlene Dunlap, 55, of Des Moines. “He’s been saying there is a flood coming for 30 years.”

What Ron Paul, who will not run for reelection to his Texas congressional seat in 2012, has not done is win a statewide race, a feat that his son has accomplished.

According to the latest polls, candidate Paul has seen his Iowa support double since 2008. But he is still viewed largely as a fringe player, even as his smaller-government, anti-tax, audit-the-Federal Reserve, pro-Constitution message has become part of mainstream GOP orthodoxy.

Paul’s strength is that he has an army of young supporters on college campuses across the country devoted to him and his message. That could make the difference for Paul on Tuesday and in the future for his son, should he ever decide to run for national office.

For now, supporters are focusing on getting Rep. Paul out of Iowa with a strong finish.

But they do have visions for the future. “When we think about who could run as a VP with Ron Paul, that would be a very short list,” Pearson said. “I would love a Paul and Paul ticket.”