On the surface, Lindsey Graham’s increasingly likely 2016 presidential campaign doesn’t make much sense. Every four years, an important senator — and the South Carolina Republican certainly counts as one — runs for president without much chance of success.

You can see why a House backbencher like Dennis Kucinich or Bob Dornan might take a flier on the primaries. But what did Richard Lugar, Orrin Hatch, Bob Graham or Chris Dodd have to gain? (At least Joe Biden got the vice presidency out of his hopeless 2008 campaign.)