The New York Times projects a national popular vote margin of roughly 8.5% for the Democrats. The FiveThirtyEight average for the generic congressional ballot gave Democrats a 8.7% lead.
Sam Wang notes the popular vote margin in the last four midterm elections which were considered wave elections:
- 1994: R+7.1%
- 2006: D+8.0%
- 2010: R+7.2%
- 2014: R+5.7%
By historical staandards, that would be a wave election for the Democrats.
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