Page A1 of Sunday’s New York Times reflected a new phase in the Democratic presidential campaign: “Clinton Team Starts to Ponder Names for Her Running Mate.” At the same time, the increasing likelihood that Hillary Clinton will get the Democratic nomination has people speculating on whether and how she can appeal to Bernie Sanders supporters. The latest political sport has involved combining the two issues, suggesting that Hillary could choose a VP to her left to appeal to Sanders voters and “unite” the party.
Strategically, politicians could take a lesson from the actual sport of basketball. From the youngest kids to the NBA, coaches universally teach the strategy of “boxing out,” in which you use your body to block your opponent from desirable parts of the court. Charles Barkley was a legendary rebounder despite regularly competing for missed shots with opponents a half-foot taller. He accomplished this, in part, by boxing out: using his body to block opponents out of prime rebounding position and thereby controlling more court space.
Anyone who watches The Price is Right is familiar with this kind of strategy. If the highest price bid for an item by the first three contestants is $600, the fourth contestant, by bidding $601, partially boxes out the other contestants by controlling $601 to infinity because the rules are that if your bid is over the actual price of the item you can’t win. Even if that contestant thinks the item costs $800, the bid of $601 encompasses another $200 of bids. When the last bidder screws up – like bidding $599 instead of $601 – the audience lets out a collective groan. But that rarely happens.
Strategically, the political spectrum is similar to a basketball court, or a pricing game. In addition to staking out a specific position, candidates are trying to cover additional territory by boxing out opponents. Voters look for candidates they agree with but with only two choices in a general election, their choice may between the most agreeable (or least disagreeable) candidate and not voting.
In general, Sanders supporters are to the left of Clinton. Cruz is at the far right. Trump occupies a shifting position between right-of-center and far-right, depending on whether voters believe his statements as a conservative or his background as a moderate. He’s capable of popping up all over the court, like Dennis Rodman (who led the NBA in rebounding seven consecutive years).
Regardless of running mate, Hillary Clinton ideologically blocks out Republican candidates from picking up voters to her left. (Similarly, pro-life evangelicals on the right side of the spectrum are unlikely to jump over Trump or any other Republican candidate and embrace Clinton.) Choosing someone to her left as an accommodation to Sanders supporters doesn’t help her with either independents or more moderate Republicans. In fact, the further she makes accommodations to the left end of the spectrum, the more territory in the middle that puts in play for her Republican opponent.
Of course, there is also the argument that those Sanders voters, unlikely to move from left of Clinton to a Republican candidate, will just sit out the election. According to a poll in early April, about a quarter of Sanders voters say they won’t vote for Clinton if she is the nominee. Using back-of-the-envelope rounding, Clinton could lose 12% of Democrats, or 6% of the electorate. If she runs against Donald Trump, however, a far larger number of disaffected Republicans may be in play. An April poll in Virginia, for example, found that nearly a third of Republicans won’t vote for Trump if he gets the nomination. That’s nearly three times the number of Democrats Clinton has to worry about, more than 17% of the total voters.
These numbers are approximations, and they are likely to be overestimates because, when it comes down to one candidate from each party, voters tend to stay in-party, regardless of what they say in the heat of the battle. In magnitude, though, Clinton has a lot more potential defectors to pick off than Trump.
A pair of studies cited by a recent Wall Street Journal article, “How to Think About a Running Mate,” found that, going back to 1968 or 1976, the vice-presidential choices had an effect on the popular vote of less than 1%. Most candidates, however, have stressed party unity rather than boxing out to get the undecided middle of the spectrum. Republican Presidential candidates, in particular, have usually unified by GOP by the center-spectrum candidate choosing a VP to the right: Nixon-Agnew (1968 & 1972), GHW Bush-Quayle (1988 & 1992), Dole-Kemp (1996), McCain-Palin (2008), Romney-Ryan (2012).
The chief exception supports the box-out strategy. In 1976, Ronald Reagan, from the Far Right of the GOP, chose George H.W. Bush, representing the moderate “Eastern establishment” wing of the party. Bush opposed Reagan in the primaries and was sharply critical of his economic views. That choice unified the party, but by unifying it toward the center, it also boxed out incumbent Jimmy Carter.