Senate Minority Leader Mitch McConnell (R-Ky.) has some big things to worry about in his reelection campaign. (Read: his unpopularity and the threat of Democrat Alison Lundergan Grimes.) But on this primary day, businessman Matt Bevin (R) isn't one.
Let's look at these factors one at a time.
1. Bevin stumbled. Again and again.
Flash back to August of 2013. Things were looking up for Bevin. He gave a well-received speech at the annual Fancy Farm picnic. He was starting to catch the eye of national tea party groups. But his promise would be short-lived — in large part because of distractions he could have avoided.
Bevin suggested that legalizing gay marriage could lead to parents being able to marry their children in a February radio interview. He spoke at a pro-cockfighting rally. He was repeatedly dogged by his past support for the TARP bank bailout program that he bashes these days. On and on it went. (And, yes, credit for it going on and on goes to McConnell's opposition research team.)
To convince voters to fire a long-serving incumbent requires more than just persuading them the other guy is awful. You have to be a palatable-enough alternative. Time and time again, Bevin fell short of making that case as he veered off-message, and doubts arose about his own limited record.
2. McConnell didn't make any major screw-ups.
When Dick Lugar lost in the Indiana GOP Senate primary in 2012, there was a laundry list of reasons why it happened. He thumbed his nose at the tea party. He failed to put to rest concerns about his residency. He was writing op-eds about foreign policy in the Wall Street Journal when that was the last thing Republican primary voters back home cared about.
McConnell learned the lessons of Lugar's loss. He secured the support of tea party hero Sen. Rand Paul (R-Ky.) early on and hired a former Paul aide to run his campaign. He spent more than $9 million and didn't get caught back on his heels the way Lugar did. And he didn't give Bevin much in the way of new fodder with his public comments and maneuverings in the Senate during the past few months.
3. The cavalry came in for McConnell.
Former McConnell hand Scott Jennings advised a nonprofit and a super PAC aligned with McConnell that spent millions on the campaign. The Chamber of Commerce spent more than $1 million on McConnell's behalf. Sure, Bevin had the Senate Conservatives Fund in his corner and spent more than $3 million from his own campaign in the race, all as McConnell was also taking heat from Democratic groups. But it was no match overall for McConnell and his allies. The era of tailor-made super PACs and nonprofits especially benefits candidates like McConnell, who have lots of well-funded allies.