Narrowly Defeating an Incumbent

Here's a question that occurs to me in light of my previous post: how often has the incumbent President narrowly lost a Presidential election? Well, let's run down the list. When Bill Clinton beat George Bush, he did so by a 5.5% popular-vote margin, equivalent to a 6.8% margin among the two-party vote, and scored 2.2 times as many electoral votes as Bush. Moreover, Bush managed only 37.5% of the overall popular vote, due to Ross Perot's third-party bid. Ronald Reagan beat Jimmy Carter by nearly 10 points, and got 10 times Carter's electoral tally. In 1968 Lyndon Johnson didn't even make it to the general election (this has happened other times). Franklin Roosevelt won 57.4% against Herbert Hoover, who fell under 40% and carried just eight states worth 59 electors. In the wacky three-way of 1912, William Howard Taft won a stunning eight electors on the "strength" of his 23.2% popular-vote showing. In 1828 Andrew Jackson crushed John Quincy Adams 178-83 in the electoral college, and 56% to 43.6% in votes.

That leaves us with just a few examples. In 1840, William Henry Harrison (who had come within 4000 votes in Pennsylvania of becoming President four years earlier) beat Martin Van Buren by a 6-point margin popularly and a roughly 4-1 margin in the electoral college. In 1800 Thomas Jefferson and the Democratic-Republicans won 73 electors to President John Adams' 65, a very narrow margin; however, in the handful of states irregularly allowing popular votes, Jefferson won over 60% of the vote. Then you had the Cleveland-Harrison festival, where Harrison "beat" Cleveland by a "margin" of negative 0.8% in the popular vote, and just 233-168 in EV's, and then Cleveland beat Harrison by a 3% margin, taking 277 EV's to Harrison's 145. I'm tempted to throw those elections out, since Cleveland won the popular vote in both of them. Likewise, since in Jefferson's day the popular vote didn't really exist, I'm tempted to throw that out, too.

We're left with the 1840 and 1992 elections, which featured popular-vote margins of roughly 6% and much more landslide-style electoral college performances. In other words, it's rare. When an incumbent President loses, they tend to lose big. And I may be a bit of an optimist here, but I doubt Obama is going to lose big in 2012. Maybe he will: maybe the economy will get that much worse, and Romney will somehow run a strong campaign. Interestingly, I also once found the converse, i.e. when incumbent Presidents win re-election they usually increase their original margin of victory. I guess close elections featuring incumbents are just pretty rare. This makes sense on the prevailing theory, that when times are good or getting better you just re-elect the incumbent and when times are bad and getting worse you dump them for the other guy. The 2012 election is weird, then, in that times are bad, getting better at an unacceptably slow pace, and the alternative is considered, well, awful. So perhaps there just isn't that much precedent on the subject. In any event such historical precedents don't actually have much predictive value, since there are always lots of them on both sides, but it's an interesting result nonetheless.