A big part of the reason why is that elsewhere across the 2016 map, it’s looking like slim pickings for conservatives. These groups tend to prefer playing in safe, red states where opponents of their candidates can’t rebut with an electability argument about winning the general election. Given the blue hue of the 2016 Senate map, a number of more moderate Republicans may get some protection from that. Others have wised up to the mistakes of their colleagues and gotten out of the gate early to raise money and rally support within the GOP.

“Honestly, I think it’s going to be a relatively small map,” said one conservative strategist who asked not to be named. “But in the end, it may wind up playing better into conservatives’ hands, in that you may see a better concentration of funding and resources and bodies on the ground in just a few states instead of a lot of states.”

Horowitz noted that McCain is conservatives’ first shot at a second chance, a test balloon for whether you can “slow bleed” an incumbent over multiple election cycles. After losing the 2008 presidential race, McCain tacked to the right in 2009 and 2010 before his challenge from Hayworth. The maneuvering included a memorable TV ad in which McCain said he would “complete the danged fence” along Arizona’s border with Mexico. But his cosponsorship of the Senate’s comprehensive immigration reform bill will be fresher in conservatives’ minds, among other recent actions.