Apparently Joe Biden is thinking of running for president in 2016. He should. Yes, he'll be 74, and, no, I don't know if he'd make a good president. But it's the way of Democratic vice-presidents. As opposed to Republican ones.

Since 1972, when more open primary rules were first enacted, three Democrats have been elected president: Carter, Clinton and Obama. In the case of the first two, in the election after their last election, the nomination went to their vice president: Mondale in '84 and Gore in '00. Neither won.

This was true for Reagan's veep as well: George H.W. Bush ran and won in '88.

Since then? Bush's veep, Quayle, sputtered in '96 and never got out of the starting gate. He was considered a lightweight with no shot. Still is. W's veep, Cheney, never ran. He was considered a horrible heavyweight with no shot. Still is. Darth Cheney, who chose himself veep. The lightweight was the president.

There's always a lightweight on the Republican ticket, isn't there: a “folksy” someone, generally, who isn't that smart. Each election you think it can't get worse and then it does. It can't get worse than Reagan, you think, and then they choose Quayle. It can't get worse than Quayle, you think, and then they choose W. OK, W's gotta be the bottom, right? Hello, Sarah Palin.

Dems are always a little more serious about who might be a heartbeat away. Or who might be the heartbeat.

So I can see Biden in 2016, although I'm more intrigued by Hillary.

As for the Republicans in 2012? This certainly wouldn't break the trend: