Rand Paul elicited guffaws from the liberal blogosphere after stumbling when asked why he endorsed Senate Minority Leader Mitch McConnell.
"Because he asked me," Kentucky's junior Republican senator told Glenn Beck. "He asked me when there was nobody else in the race, and I said yes."
The answer was reminiscent of then-South Carolina Gov. Mark Sanford struggling to explain his support for John McCain in 2008, or Ted Kennedy's inability to tell Roger Mudd why he was running for president in 1980.
Yet for libertarian-leaning Republicans like Rand Paul, supporting McConnell or his primary challenger Matt Bevin is not as straightforward a question as it initially seems.
Bevin has recently gained some momentum, moving from a longshot to one of the tea party's biggest candidates this year. He has taken most of the right positions, won the support of FreedomWorks and other conservative groups frequently aligned with Paul, and pressed for Republicans to work harder to cut spending and repeal Obamacare.
McConnell, by contrast, sided against tea party favorite Ted Cruz on the debt ceiling increase and procedural votes on Obamacare defunding. More importantly, the Republican leader worked during Kentucky's 2010 GOP primary to keep Paul out of the Senate in the first place.
There is nevertheless a libertarian Republican case to be made for McConnell. First, he has always been a fairly conservative member of the leadership team. Protecting free political speech against campaign finance reform laws has always been one of his main causes. That's not exactly a statist position.
Numerous reports have suggested McConnell has laid the groundwork for Obamacare repeal if Republicans retake the Senate, even though his differences with Cruz have made conservatives skeptical. After the Supreme Court upheld the health care law, McConnell was said to be on board with unwinding it via the reconciliation process.
McConnell is also the Republican leader who has been most swayed by Rand Paul's success. The two men made peace after the 2010 primary. McConnell appeared in the 2012 Republican National Convention video tribute to the junior senator's father, presidential candidate Ron Paul.
McConnell also appeared at the elder Paul's congressional retirement dinner, helping him secure a Library of Congress room as a venue. He hired Jesse Benton, who had worked for both Pauls, as his 2014 campaign manager.
The Senate Republican leader has also moved in Paul's direction on substantive issues. He supported Rand Paul's filibuster on drone use, appearing on the floor to say, "I think it's entirely appropriate that the senator from Kentucky engage in an extended debate with the support of his colleagues."
McConnell broke with House Speaker John Boehner and House Majority Leader Eric Cantor in opposing a resolution that would have allowed President Obama to use military force against Syria. The Washington Post described him as an "odd man out," but the war never happened due to a lack of congressional support.
Critics charge that some of Bevin's tea party positions are of recent vintage. The biggest controversy surrounds a letter the challenger signed in his capacity as an investment fund president describing the 2008 Troubled Assets Relief Program as "positive" and saying "don't call it a bailout."
The bigger issue, however, is how to change the Republican Party. The most obvious way is for libertarians and tea party conservatives to elect like-minded Republicans, like Bevin, to replace the old guard. That's how Paul got elected and it will remain an important part of any insurgent strategy within the party.
But moving the center of gravity within the GOP also requires winning over some of the older Republicans, including even the establishment. That can take place through changing minds or just convincing incumbents it's a matter of political survival.
"I'm willing to be another Ronald Reagan if that's what you want me to be," Bob Dole once vowed. Dole's successors may promise to be another Ron or Rand Paul.
Establishment support would be helpful to a Paul 2016 presidential campaign. It would also help entrench Paulite ideas in the GOP platform. Whatever his flaws, Mitch McConnell is an obvious candidate for helping to bridge that divide.
So if Rand Paul seems confused about who to support in the Kentucky senatorial primary, there's good reason. More of his supporters should feel similarly conflicted.
W. James Antle III is editor of the Daily Caller News Foundation and author of Devouring Freedom: Can Big Government Ever Be Stopped?