From The Washington Post:
Mitt Romney's selection of a vice-presidential running mate, which he is expected to announce soon, could shed valuable light on how he makes big decisions. His choice could shore up what voters view as weaknesses or double down on what they perceive as strengths. In a 2010 study of post-election voter surveys from 1968 to 2008, University of California,  Irvine political scientists Bernard Grofman and Reuben Kline "find that the net impact of vice-presidential selection is at most one point." Not trivial, but probably not decisive. "It makes a very small difference," said James Campbell, a political science professor at the State University of New York at Buffalo, who has also studied vice presidential choices.

For the full story, please visit http://www.washingtonpost.com/politics/for-romney-history-suggests-vp-pi....