A new historical calculation of Mitt Romney’s chances to take a third stab at the presidency and win puts the Republican’s chances of victory at a tiny 7 percent, probably not even worth the effort of stamping out Mitt 2016 buttons.

As allies, encouraged by voter polls, continue to push him to run again, the facts are that only nine one-time nominees have ever won the nomination a second time, and only four of those won the presidency. That’s four of 57 presidential elections. The last was Richard Nixon.