The first six months of 2013 have made two things very clear: 1) Rand Paul is running for president and 2) Rand Paul is the most interesting politician in the country at the moment.

From his filibuster over drones to his positioning on the immigration reform bill to his well-received trips to early presidential-voting states, Paul has shown a knack for simultaneously confounding expectations and drawing press attention. And, with the immigration fight in the Senate headed to a conclusion in the next few weeks and the debt ceiling battle looming this fall, Paul promises to be at the center of the political conversation going forward, too.

"Rand wants to accomplish things, not merely blow up the process in order to make news," said Billy Piper, former chief of staff to Senate Majority Leader Mitch McConnell. "That is refreshing and I think helps explain why so many on the right have been drawn to his leadership and style."

Paul is, without question, a prime mover in two arenas right now: the Senate and the presidential race. (Of course, the Senate is also a proving ground/minefield for several members of the 2016 presidential field so the two arenas are deeply intertwined.)

Paul's filibuster of CIA director John Brennan's nomination earlier this year proves his power in both spaces. Not only did Paul demonstrate his status as the first among equals with the tea party-aligned crowd that includes the likes of Ted Cruz (Texas) and Mike Lee (Utah) but he also showed that he acts and other 2016ers react. That includes Marco Rubio (Fla.), the man most Republicans regard as the frontrunner for the GOP presidential nomination, who went to the floor to support Paul's filibuster (and to make sure there wasn't much rhetorical space between he and the senator from Kentucky when it came to criticizing the Obama Administration).

"No 2016er has helped himself more than Rand Paul in last 8 months," said one senior Republican operative granted anonymity to speak candidly about the 2016 field.  "He has methodically put himself on track to being serious contender for GOP nomination in 2016. If the next 18 months are similar to the last couple, his presidential campaign will be much different than his father's."

What Republicans -- establishment-types and others -- find most intriguing about Paul is his potential to appeal in directions and demographics (civil libertarians, young people etc.) that get the party beyond the coalition built by Ronald Reagan in the 1980s. (We've written lots of late on the growing libertarian strain in the country and Paul is the elected official most closely aligned with those views.)

Here's Paul describing his vision of a new Republican party in an interview last month with Spencer Ackerman: "The way we’re going to compete is by running people for office who can appreciate some issues that attract young people and independents: civil liberties, as well as a less aggressive foreign policy, not putting people in jail for marijuana, a much more tolerant type of point of view."

And here's a veteran Senate political operative on Paul's potential appeal: "Rand is the first real candidate in thirty years with the potential to alter Reagan's three-legged stool of defense hawks, fiscal conservatives, and social conservatives. He really has a modern appeal that has a much higher ceiling with today's electorate than anyone else in the party right now."

Whether Rand Paul winds up as a top-tier presidential candidate in 2016 -- we think he will be -- it's clear he is someone who has not only avoided being pigeonholed on any one issue but also leapt over the expectations many people had for him when he was first elected in 2010.

"He has continually been underestimated politically over the past four years and easily crossed the bar each time," said Jon Deuser, a longtime Republican consultant with Kentucky ties. "I think he fascinates us because he is so un-Washington and doesn't easily fit into the usual left-right cubby holes."

Here's where Paul fits at the moment: he is the most interesting person in the Republican political world.  And that's a good place to be.