A good piece in Politico  about the evolution of Haley Barbour's decision not to run for president.

Despite most of the signs pointing to a run beginning next week, those closest to Barbour believe he simply didn't have the desire to - as Barbour put it - give a "10 year commitment" to the presidency:

But even as he was taking all the usual steps - calling donors, visiting early states, hiring operatives - there were signs that the Mississippian wasn't all in.

As he traveled the country testing the waters over the last few months he had begun privately using the same phrase to describe his intense exploratory schedule: he called it his "death march," a Republican who heard Barbour use the term recalled.

[...]

"I'm not somebody who's been dying to run for president all his life," the normally amiable Barbour said with a tinge of annoyance at an impromptu press availability under the bleachers of a high school gym. "I have a real life. I have a family. I've had two great careers. Before I make a final decision, I'm going to make sure that I feel the call strongly enough, got enough fire in the belly that I'm ready to make a 10-year commitment which is what this is. It's a 10-year commitment."

It would, in short, dramatically change his life at the age of 63. Barbour, who lost his father at age two, knew that if he became president it would take up a chunk of his remaining years.

His own wife and one of his two sons were unambiguous about where they came down - they were against the idea.

There may be another, more mundane reason for Barbour's hesitancy; political calculation. Haley Barbour has been making these calculations for 30 years for other people - is there a realistic path to win the nomination, or can I get to 270 electoral votes? It's a good bet that privately, he doubted his ability to do either - perhaps without changing who he was. 

If a northerner like Romney or Pawlenty were to get the nomination, it is possible that Barbour will be seriously considered for the 2nd spot on the ticket, although such regional considerations are a lot less important today than they were a few election cycles ago. In any event, a GOP candidate could do worse than asking Haley Barbour for advice. He is easily one of the best politicians in the country and could help any Republican get elected president.