Sen. Rand Paul (R-Ky.). (AP Photo/Manuel Balce Ceneta)

As Sen. Rand Paul (R-Ky.) seriously weighs a run for president, it's becoming increasingly clear the two people with the most potential to shape his political future are his father and his wife.

Ron Paul and Kelley Paul promise to influence Paul's future in very different, very notable ways. Kelley Paul's apparent reservations about her husband running for president appear to be all that could prevent him from making a White House bid. Ron Paul, who has adopted positions and made comments that are out of the mainstream, could prove to be a big distraction in a presidential campaign.

Both points ring true in Ryan Lizza's new lengthy profile of Paul in the New Yorker. As Paul's political adviser Doug Stafford told Lizza, "Unless Kelley says no, he’s running.”

Kelley Paul has made no secret of that fact that she sees the downsides of a presidential campaign and the intense national scrutiny that comes with it.

"I mean, it's something that you don't go into lightly, being in the public eye is hard on a family and a marriage," she told WKU public radio in Kentucky over the summer. "I'm really proud of Rand, I think he's doing an amazing job, so I'd love for him to be able to expand that but we still have a few hurdles to cross before we actually pull the trigger on it."

Everything Paul says and does suggests he's gearing up for a run. He's visiting Iowa and New Hampshire. He's giving sweeping speeches on issues he cares about. He's happily claimed the mantle of the party's leading skeptic of sweeping government surveillance and a hawkish foreign policy prescriptions.

But none of that groundwork will lead to a presidential campaign, it appears, unless Kelley Paul is 100 percent on board.

If she is, and if he runs, another member of the Paul family will be a key player: Paul's father Ron.

Ron Paul, a former Texas Republican congressman, ran for president in 2008 and 2012 -- but never with the potential for winning that his son has right now. The Kentucky senator has spent most of the last two years building bridges with the same GOP political establishment that largely shunned his father and viewed him as an annoyance. He's had a lot of success. But his father could undercut that.

Lizza captures it well in his story. (Emphasis ours):

As I was waiting for Paul to finish a meeting, I told two of his aides about an e-mail that had been sent to reporters during his speech. It was from a public-relations firm working for Ron Paul, also a doctor, who had recently written a column for his Web site explaining why he thought Russia wasn’t responsible for downing Malaysia Airlines Flight No. 17, in Ukraine. “In the interview, Dr. Paul will defend his controversial comments on Putin and voice his support of non-interventionist foreign policy,” the e-mail said. Even as Rand was working to rebrand himself, his father was unintentionally undercutting the effort. Rand’s aides were caught off guard. “It’s good to see that the old man is still out there speaking his mind,” one said.

Paul’s relationship with his father is a sensitive issue. A couple of weeks before his speech to the Urban League, Paul was sitting at a conference table in his Capitol Hill office suite complaining about his press coverage. He was agitated about a story in the Times, earlier this year, which traced his intellectual lineage by reporting on many of the fringe groups and individuals with which his father has been associated during his career, including the John Birch Society and various writers who “championed the Confederacy.”

“I really was disappointed,” Rand said, his voice rising. There was a quote “from some guy who I’ve never met saying something about how slaves should have been happy singing and dancing because they got good food or something. Like, O.K., so now I’m in the New York Times and you’re associating me with some person who I don’t know.” He went on, “It’s one thing to go back and interview my college professor or groups that I actually was with. But I was never associated with any of these people. Ever. Only through being related to my dad, who had association with them.”

Ron Paul has never been one to pull punches or not speak his mind. That could be one of the biggest challenges for the younger Paul should he run for president. The same brand of unrestrained candor that many of the most enthusiastic Paul supports find refreshing could be troubling to the larger GOP electorate -- and potentially the general electorate.