If Jeb Bush chooses not to run, which appears increasingly to be the case, then the GOP establishment will be left without an obvious leading candidate. Sure, Governors Chris Christie, Rick Perry, Scott Walker, Bobby Jindal, Mike Pence, and John Kasich are all positioning for possible runs, but chances are that none of them will go the distance.
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Meanwhile, among the conservative senators vying for support from the Tea Party — namely, Rand Paul, Ted Cruz, and Marco Rubio — only Paul seems likely to gain any real traction. In fact, among the full potential field of GOP presidential candidates, Paul has done more than any other to advance his cause over the past summer by reaching out to groups beyond his traditional narrow band of support who are sympathetic to some of his libertarian positions, such as African-Americans, Silicon Valley technology executives, and college students.
With no establishment candidate catching fire and Paul emerging as the frontrunner heading into the 2016 Republican primaries, the GOP establishment's elders would become uncomfortable since they view Paul as too far outside of the mainstream to be their nominee. While these party leaders would prefer not to violate the GOP's famous Eleventh Commandment — "Thou shat not speak ill of any Republican" — they would assuredly not sit idly by and allow Paul to march on to the Cleveland convention. Instead, people like Jeb Bush and Mitt Romney, who hold great sway over the party's donors and campaign infrastructure, would likely come together and play the role of kingmaker by anointing a candidate of their own. And the person they almost certainly would choose is Romney's former running mate, Congressman Paul Ryan.
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Ryan is not actively campaigning for president despite recently publishing a book, which has become an unofficial requirement in recent election cycles. Nevertheless, if Romney, Bush, and other party luminaries asked Ryan to run "for the good of the country," it is hard to believe that he would say no.
Ryan has thus far eschewed a House leadership role due, at least, in part, to his commitment to his young family that remains in Janesville, Wisconsin and to whom he returns to from Washington every weekend. If Ryan took a congressional leadership post, he would need to spend much of his time traveling around the country for fundraisers. Likewise, he is believed to not be interested in spending the demanding time on the campaign trail that is required to run for president. However, in this scenario, the duration he would have to campaign would be truncated as it would not begin until the primaries are already underway. And if Ryan ended up in the White House, he would actually see his family more often than he does now since he could eat dinner with them every night.
It is possible that it would be too late for Ryan to enter the race once the primaries had started and Paul could have developed too great of a lead already. In contrast, though, to a general election in which retail politics dominate, the GOP nominating process is more of an insiders' game, in which access to party fundraising and infrastructure almost always dictates the outcome.
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Ryan would be far from guaranteed to best Clinton as she would still remain the one to beat, but he could certainly give her a run for her (considerable) money. Just imagine the optics on the debate stage — a P90X using "young gun" towering over a near septuagenarian with lingering questions about her health. Plus, it is unusual for the American people to choose a president from an older generation than the one currently in office — the last time it occurred was when Reagan followed Jimmy Carter in 1980 and prior to that, you have to go back to when James Buchanan succeeded Franklin Pierce in 1857.
For now, Ryan seems focused on pursuing tax reform by becoming the next chairman of the House Ways and Means Committee. But just last week, he said, "Typically tax reform in history has been led by presidents." If Ryan is so dedicated to tax reform, the one way that he could have a chance of making it happen more than by taking the gavel of the Ways and Means Committee is to be the one sitting behind the Resolute desk in the Oval Office.