At FiveThirtyEight, Andrew Gelman has an intriguing post analyzing the approval ratings of governors as a function of state population. Long story short: small-state governors typically have higher approval ratings than large state governors. (See: Schwarzenegger, Arnold; Paterson, David; Hoeven, John.)

Gelman offers a few possible explanations:
Some theories: in a large state, there will be more ambitious politicians on the other side, eager to knock off the incumbent governor; small states often have part-time legislatures and thus the governor is involved in less political conflict; small states (notably Alaska) tend to get more funds per capita from the federal government, and it's easier to be popular when you can disburse more funds; large states tend to be more heterogeneous and so it's harder to keep all the voters happy. As the graphs show, the pattern isn't perfect, but it looks real to me. Next step is to get data from other years.

At least one other theory I'd throw in there: small-state governors personally meet more of their constituents while campaigning than large-state governors do. (Governors in states like California, Florida or New York, by contrast, can bombard the airwaves with ads and lobby for business and labor endorsements.) It seems logical that the more a voter meets a politician personally, the more likely he is to give him or her the benefit of the doubt in political controversies.

A penchant for "retail politics," by the way, can't hurt in Iowa or New Hampshire either...