Special elections aren't crystal balls

[Bloomberg]( Follow Us [Get the newsletter]( Get Jonathan Bernstein’s newsletter every morning in your inbox. [Click here to subscribe]( There’s a [special election in New Mexico’s 1st Congressional District]( on Tuesday, with voters choosing a replacement for Interior Secretary Deb Haaland in the U.S. House of Representatives. It’s not the first special election of the year, but it does seem to be getting a fair [amount]( of [coverage,]( with both parties poised to make all sorts of claims about future elections if things go their way. Don’t buy the hype. Every House seat is important, especially given the narrow Democratic majority, so an upset by Republican Mark Moores would be real news and make Speaker Nancy Pelosi’s job even more difficult (although it’s worth noting that the House Democrats haven’t had much trouble staying united so far, perhaps because Pelosi is good at her job). But neither a Moores win nor a narrow loss would tell us anything about 2022; nor would an unexpectedly large win by Democrat Melanie Stansbury be a valuable clue to future elections. The political science is straightforward. No single special election predicts much. The overall results of all special elections over the two-year cycle in the run-up to a midterm election does tend to be correlated with the outcome those midterms — at least, once adjusted for the normal partisan lean of the districts that happen to have elections. But they don’t reveal anything that can’t already be learned from polling. For example, Democrats did well in the two years leading up to the 2018 midterms, generally by losing by less than the typical margin of the Republican districts that had vacancies. They also did well in the regularly scheduled 2017 elections. However, that didn’t really add to what we already knew from public opinion polls: that Donald Trump was an unusually unpopular president, and that “generic” ballot tests (that is, asking people if they intended to vote for a Republican or Democratic candidate) looked promising for Democrats. At best, special elections provide a partial reality check on polling. If, for example, President Joe Biden continued to be relatively popular according to surveys, but Democrats were getting clobbered whenever people were actually voting, it might be a sign that something was amiss. Not, however, if one or two special elections went well for Republicans; that might just be about local factors affecting particular campaigns or candidates. The same is true about campaign advertising. If the Democrats do well in New Mexico, it won’t prove anything about the environmental policies Stansbury has been running on. Nor will we learn much about Moores’s campaign against “defunding” police if Republicans do well. What we can learn, at least a little, is what the parties consider good policy areas for their candidates to talk about. That can be important, and it’s often possible to pick up new policy priorities from these elections. But candidates can do well despite choosing advertising themes that don’t really help them, and vice-versa, and any accurate analysis of how particular issues are playing with the electorate needs to be a lot more sophisticated than just assuming that ads drove the results. That said, an analysis of what happened in an election doesn’t have to be accurate to be accepted by party actors and influence their future decisions, as the political scientist Seth Masket [has reminded us](. The outcome of any House race is important, and there can be plenty of other reasons to pay attention to special elections. Just don’t buy any hype about how they might predict future elections. 1. Amrita Basu at the Monkey Cage on Indian Prime Minister [Narendra Modi’s style](. 2. Matthew Shugart on [forming a government in Israel](. 3. Ed Kilgore with an excellent history lesson about [Newt Gingrich and 1994](. 4. Noah Smith on [inflation](. 5. And my Bloomberg Opinion colleague Noah Feldman on [Florida’s new social media law](. Get Early Returns every morning in your inbox. [Click here to subscribe](. Also subscribe to [Bloomberg All Access]( and get much, much more. You’ll receive our unmatched global news coverage and two in-depth daily newsletters, the Bloomberg Open and the Bloomberg Close. Paid Post The power of PayPal online, now in person. Give your small business an easy way to accept touch-free, in-person payments. Create a unique QR code with the PayPal app and display it on your device or as a printout in store. [Download the app.]( Customer must have PayPal account and app to pay. PayPal  Before it’s here, it’s on the Bloomberg Terminal. Find out more about how the Terminal delivers information and analysis that financial professionals can’t find anywhere else. [Learn more](.  You received this message because you are subscribed to Bloomberg's Early Returns newsletter. [Unsubscribe]( | [Bloomberg.com]( | [Contact Us]( Bloomberg L.P. 731 Lexington, New York, NY, 10022