One assumption about Romney has been that if he (or anyone else) were selected as McCain’s VP, he would be in pole position for a run at the presidency next time around (whether 2012 or 2016). Most people trumpet this as if it’s received wisdom, but how much sense does that really make?

Incumbent VPs from the last 70 years fall into one of several categories:

• Succeed sitting president through death or resignation (Truman, Johnson, Ford)
• Seek and win nomination, win election (Nixon, Bush)
• Seek and win nomination, lose election (Humphrey, Nixon, Mondale, Gore)
• Seek and fail to win nomination (Quayle)
• No running for presidential office (Cheney, Rockefeller, Barkley)
• Resign while in office (Agnew)

Eight of these 13 men have therefore gone on either to be the nominee of their party or president, which seems good odds. But of those, four lost at least their first attempts to be elected to the presidency, and three became president through no fault or merit of their own. Just two of them – Bush and Nixon – actually won election in their own rights.

The records in office of those that did become president are not stellar:

• Truman may be the exception, at least in some eyes, although he failed to win re-election for a second term
• Johnson (who failed to be elected to a second term in his own right and presided over several miserable failures)
• Nixon disgraced the office and his party
• Ford replaced him and unsurprisingly failed to be elected in his own right even once
• Bush won on Reagan’s coattails, but again failed to win a second term.

Taken together, none of this suggests either that VPs are more likely to be elected than anyone else (for example former Governors, who have been elected four of the last five times), or that they make particularly good presidents when they are elected. Romney, Huckabee and others (especially John McCain) should all bear this in mind.

Now, part of the problem is the kind of men chosen as VPs, often more for the states they can bring in, their unlikeliness to challenge the candidate in the personal dynamism stakes, and the balance they bring to the ticket rather than any admirable qualities they possess in their own rights. Romney might prove the exception to that rule, although Huckabee arguably fits the mold better in some ways. But anyone assuming that the Vice Presidency is the best path to the presidency is making a shaky assumption at best. I’m glad to see that Romney is also setting up a PAC to elect Republican candidates as a way of shoring up his other main option for setting himself up for 2012.