Take a look at every president’s net approval rating (approval – disapproval) since the end of World War II. Biden’s at about -9 points net approval rating right now. Specifically, we’ll examine all elected presidents at this point into their first term and compare that to where they stood during their first midterm.
It turns out that among elected presidents there’s actually a pretty clear correlation (+0.83 on a scale of -1 to +1) between their net approval rating at this point and a year from now. Most presidents tended to lose ground from this point forward. The average president saw his net approval rating drop by 13 points.
Now, there is a wide spread here between how presidential approval ratings changed. Some — like Bill Clinton in 1993, Richard Nixon in 1969 and Dwight Eisenhower in 1953 — basically held their ground at this point through the midterms. Others like John F. Kennedy in 1961, Jimmy Carter in 1977 and Barack Obama in 2009 saw double-digit declines.
Just one, Donald Trump in 2017, picked up appreciable support (i.e. more than 5 points) in the year before the midterm. He gained about 9 points from a nearly -20 net approval rating to about -10 points.
It shouldn’t be too surprising that Trump was the only one to really see an uptick in his popularity. Over the long term, approval ratings tend to revert to the point where half the population likes someone and half dislikes. Because most presidents are popular at this point, it makes sense that their approval ratings decline. Because Trump was unpopular at this point, his approval rating had a better chance of going up.
It seems more likely than usual for Biden to see some improvement in his popularity compared to most presidents. A simple statistical model predicts just that. It has Biden getting to about a -5 point net approval rating compared to the -9 net approval rating right now. Additionally, the dataset is relatively small (at just 10 presidents), so Biden could prove to be an outlier.
Still, Biden shouldn’t be looking to Trump for too much inspiration. Beyond the fact that Trump was still unpopular come the 2018 midterms, Trump had an approval rating of 80% among Republicans at this time. Biden is in the 90s with Democrats. All Trump needed to do was coalesce his base to be in a better position. Biden’s already done that.
The other worrisome sign for Democrats is the generic congressional ballot. The two parties are basically tied on it now in an average of polls.
History is not on the Democrats’ side on this metric, either. If you were to plot the generic ballot at this point in every midterm, for which polling data is available, since 1938 against the final margin in the House popular vote, you’d see a clear pattern. The correlation here is +0.9 (on a scale of -1 to +1).
The party in the White House usually loses ground on the generic congressional ballot from this point until the midterm. There are exceptions to that rule, but it’s almost always when the White House Party faces a large deficit to begin with.
In the average year, you’d expect a tie on the generic congressional ballot to translate to the party in the White House losing the national House vote by about 5 points. That would almost certainly translate to a significant Republican advantage in the House.
When you look over all the data, there have been six examples in the polling era where the party in the White House held on to their House majority in a midterm. In all six of them, the party was polling better on the generic ballot than Democrats are right now.
In fact, in all but one (2002), the party had a double-digit advantage on the generic congressional ballot.
The generic ballot at this point (basically a tie) looks a lot more like the generic ballot in the midterms where the party in power lost its House majority (a 4 point deficit on average) than the ones where it held onto their majority (a 17 point lead on average).
Again, the hope for Democrats is that 2022 breaks the historical trends. History can guide us, but it’s only a guide. Biden ending up with a positive net approval rating or Democrats winning the House popular vote is within the margin of error when you model out past midterms and apply those trends to 2022.
But right now, the best bet is Republicans doing quite well in 2022.