Here is Where Joe Biden is Most Likely to Find his Running Mate | Opinion

With Joe Biden all but locking up the Democratic nomination, attention has quickly turned to his vice president selection. Biden has already limited the field, announcing that he will only choose a woman. While the choice may seem open, it is worth noting Democrats have long looked to one place for a running mate: the U.S. Senate.

With one solitary exception, every Democrat since 1940 has opted for a sitting U.S. Senator as their first choice for Vice President. From Tim Kaine all the way back to Harry Truman, the Senate has served as the recruiting place for running mates. The only exception was Congresswoman Geraldine Ferraro in 1984, though in 1972, the Democratic first choice, Senator Thomas Eagleton, quit the ticket and was replaced by non-Senator Sargent Shriver.

Even before that, Democrats always looked to high-level elective and appointed federal officeholders for candidates, choosing the Speaker of the House and a cabinet member. The last time a sitting Governor was chosen was in 1924, when William Jennings Bryan's brother, Nebraska's Charles Bryan, was selected. The last time the Democrats tapped someone who wasn't in any office at the time of the selection? Failed Indiana Governor candidate John Kern, all the way back in 1908.

The Republicans take a very different tack. In the last 40 years, three of the seven vice presidential nominees—Dick Cheney, Jack Kemp, George H.W. Bush—were out of office when they were chosen. Two of the others were Governors, and only one—Dan Quayle—had served in the Senate.

Why the Democrats seem to always land on a Senator is not clear. During the days when the presidential candidates were mainly former Governors, there may have been a goal to balance the ticket with someone who had foreign policy and national governmental experience. Arguably, former Georgia Governor Jimmy Carter chose Senator Walter Mondale for this reason. However, since the last five Democratic presidential nominees had served as Senators themselves, this balancing is clearly no longer makes applicable.

The reason is probably more prosaic. Senators are among the most well known officials in the party. They get significantly more national attention than Governors and almost any individual House member. Unlike Governors, they almost automatically vote on every major issue of the day, and by the time they are selected, there will be no surprises on their policy positions. Obviously, there are also twice as many Senators, which greatly increases the pool of candidates.

Unlike almost all House members, the Senators have shown that they are able to win the votes of an entire state. They also have voted on the high profile issues, such as Supreme Court judge, as well as casts votes that are more frequently decided by a small margin, all of which signals to the base that the candidate has chosen a running mate who will continue to support the party's basic ideals.

Despite the attention, polls and history have shown that is not clear that a vice presidential candidate makes a positive difference for any president. According to exit polls, two of the most controversial recent picks, Quayle and Alaska Governor Sarah Palin, may not have had any important impact on the race. Richard Nixon – one of only two people to be on a national ticket five times – thought that a vice presidential was all negative. But ever since John Adams unhappily ended up with his Thomas Jefferson, his ideological and electoral opponent, as his vice president in 1796 (under the pre-12th-Amendment rules), there has been a great need to take the vice presidential selection seriously, even if it may not pay off. This is especially true for the Democrats, whose last five Vice Presidents have gone on to subsequently become a future presidential party nominee.

Will Biden maintain this Democrats focus on Senators? While some Governors, notably Michigan's Gretchen Whitmer and other officials have been discussed, the most prominent names have been Senators like Kamala Harris Amy Klobaucher, Catherine Cortez Masto and Elizabeth Warren. Based on the recent history, no one should be surprised if he looks to the upper chamber for his pick.

Joshua Spivak is a senior fellow at the Hugh L. Carey Institute for Government Reform at Wagner College in New York. He blogs at The Recall Elections Blog.

The views expressed in this article are the author's own.