the easiest way to read a midterm is as a national progress report on the government already in power.
the president is not on the ballot, but presidential approval, the economy, cost of living, wars, immigration, and general frustration with washington usually show up in congressional races anyway.
this is also where the word “wave” matters.
a wave is not simply one party winning congress. it is when the same national mood moves dozens of unrelated races in the same direction, including districts that normally would not be competitive.
as of september, there are signs of a difficult national environment for republicans, but calling it a wave already would be premature. a september reuters ipsos poll had democrats ahead 44 to 37 on the generic congressional ballot, while trump’s approval stood at 35 percent. cook’s polling of competitive house districts had democrats ahead 49 to 47, and its current ratings still show 21 house races and seven senate races as toss ups.
the other huge variable this year is the map itself. midcycle redistricting has moved nearly 35 million americans into newly drawn house districts, meaning some of the battlefield changed before anyone even voted.
so on election night, do not just look at who wins congress.
look at margins.
look at turnout.
look at normally safe districts becoming close.
look at which issues actually moved independents.
that is how you tell whether voters simply changed a few seats or whether the country sent washington a much bigger message.