Could a libertarian be the GOP nominee in 2016 or 2020?

It sounds like Rand Paul is starting to make inroads with social conservatives and is more willing to make alliances than his father.  He also might have some organizational advantages going into Iowa next time:

Later this month Rand will return to Iowa — without his father — to deliver the keynote speech at the Iowa Faith & Freedom Coalitions spring rally — the most obvious indication yet that Sen. Paul has his own presidential ambitions.
"He loves Iowa," Sen. Paul's communications director Moira Bagley told Business Insider. "He's been out there so much, with his dad's campaign, so he's really comfortable and really happy with the people out in Iowa, and especially the evangelical groups."
In fact, Sen. Paul's overture to Iowa's social conservatives is evidence of a budding romance between the Kentucky Republican and evangelical leaders, most of whom have never been particularly taken with the elder Paul.
Business Insider has learned that Sen. Paul has even been approached about a possible trip to Israel with Christian activist David Lane, a conservative kingmaker whose "Pastor Policy Briefings" helped launch Mike Huckabee's political star in 2008.
"Rand Paul is going to inherit his dad's political assets — he's going to be very formidable," Lane told Business Insider. "Structurally, there is something that is happening inside the state Republican parties that will have to be dealt with politically."
Lane added that the Paul message of fiscal conservatism and limited government dovetail with that of social conservatives, who increasingly see the federal debt as one of the country's biggest moral ills.
"I disagree with Ron Paul on some things, but I like that he has courage," said Lane. "He has been a real steward of the money — that's why I like Rand Paul."
Lane, who supported Rick Perry and later Newt Gingrich in the 2012 primary, said that he broached the possibility of a trip to Israel with the Senator's staff as part of a larger discussion about Sen. Paul's position on the Jewish State, which has been a political landmine for the elder Paul.
"I had heard that Ron Paul and Rand Paul were anti-Israel," Lane said. "But they explained to me that the position is not anti-Israel — it's anti-foreign aid….We give a lot more money to Israel's enemies than we do to Israel."
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Sen. Paul's political positioning provides some interesting clues about what the Ron Paul Revolution 2.0 might look like. As we have previously written, Ron Paul has built up a powerful national organization that has been staging quiet coups over local and state GOP Establishments, and is now poised to have a significant delegate presence at the Republican National Convention.
Given that Ron Paul's own presidential prospects are virtually nonexistent, Rand Paul stands to inherit this formidable movement-cum-campaign organization when his father retires from Congress at the end of this year.
Which brings us back to Iowa. After this year's caucus debacle, Ron Paul supporters were elected into almost all of the key leadership posts in the state Republican Party and are expected to deliver him the bulk of Iowa's RNC delegates, giving the younger Paul powerful allies in the first-in-nation caucus state.
"The best network in the state of Iowa is Ron Paul's — they are the Republican Party in Iowa," Iowa conservative leader/talk radio host Steve Deace told Business Insider. "If Rand Paul wants to run for president, he will have that organization as a huge advantage over everyone else."
Deace, like a number of other prominent social conservatives, is deeply dissatisfied with Romney, and predicts that the GOP will lose this year's election to Barack Obama, precipitating Republican "trench warfare" that will reshape the party going into 2016.