It’s easy to list the reasons Graham—who is 59 and in his third Senate term—can’t win the GOP nomination. He’s reviled by his party’s base as a Republican in Name Only for his sometime moderation, including vocal advocacy for immigration reform and climate legislation. Tea Partiers have dubbed him “Flimsy Lindsey” and “Grahamnesty.” To many on the right, he’s the epitome of the odious Washington Republican—that breed that haunts talk-show green rooms, mingles with the chattering classes, and fetishizes bipartisan compromise for its own sake. Graham is also a confirmed bachelor who’s been known to put his sister’s family on his campaign literature. He’s not particularly tall or distinguished-looking, and he dresses like a small-town car dealer…

If you look at Graham’s record a certain way and squint, he doesn’t look quite so unlikely: military veteran, Southern Baptist, working-class roots; vocal critic of the Obama administration’s foreign policy and the 2012 Benghazi affair; native of a state that holds the third presidential nominating contest; an experienced legislator in a field short on same. (The other three senators in the race—Marco Rubio, Rand Paul, and Ted Cruz—have each been in Washington for five years or less.) Graham grew up in an apartment above his family’s pool hall and liquor store, and became his younger sister’s legal guardian when his parents both died unexpectedly while he was in college. (When they were young, he decided Darlene should spell her name “Darline” instead, and she spells it that way to this day.) Graham is a deft politician, quick on his feet and funny, and his speeches so far have impressed early-state activist audiences. McCain, who preemptively endorsed his friend back in January, predicted the onetime Air Force lawyer would “shred ’em” in the debates.