What the Generic Ballot Polls Tell Us This Far Out

G. Elliot Morris: “First, the national political environment changes a lot in the 18 months before a midterm. On average, the leading party’s margin changes by 5 points from now to next November.”

“Sometimes, the environment changes a hell of a lot — such as in 2010, when the Republicans gained 11.2 percentage points between July 2009 and November (when measuring the parties’ shares in the ballot to their eventual vote shares). Even in 2022, when we have a lot of polls so uncertainty in the average should be lower, the national environment is 6 points more Republican on election day than the generic ballot polls indicate for July 2021.”

“So, super-duper-early polls (18 months out) are not a great predictor of election results.”

“Second, note that one pattern that does hold here is that the part out of power tends to gain in the generic ballot as time goes on. Republicans gained in 2021, 2013, and 2009, when a Democrat was in the White House, and Democrats gained in 2005 and 2017, when we have a Republican president.”