The whats and whys of the 2016 presidential election have so far evaded the best predictions of pundits and pollsters.

But former president Bill Clinton didn't get his nickname "Secretary of Explaining Stuff" for nothing.

On Tuesday, he accepted a challenge from Stephen Colbert to try to explain -- quickly and casually, too -- what the heck's going on on the campaign trail, including why surprise candidates like Sen. Bernie Sanders (I-Vt.) are besting establishment candidates like Clinton's wife, Hillary Clinton.

Clinton, notably, talks about Sanders's success without talking about his wife's campaign. He also dispels a rumor that he urged GOP front-runner Donald Trump to run when the two men spoke by phone in May.

But Clinton admits that it would have been a positively genius -- others might say Clintonian -- move.