Traders certain Republicans will hold fewer than 190 House seats in the midterms

The Associated Press called Texas' 23rd Congressional District early Wednesday for Democrat Katy Padilla Stout, who defeated Republican Brandon Herrera. The call flipped a seat Republicans held, and The Texas Tribune also reported the result. The AP call added to a string of Democratic gains but did not by itself show where the Republican total will end up.

Traders now treat Republicans finishing with fewer than 190 House seats as certain, though the outcome has not been decided. Expectations have shifted sharply. The outcome was unlikely to within reach through the weekend and stayed short of a toss-up on Monday. Late Tuesday, as the first results arrived, expectations surged to likely, then to all but certain in the small hours of Wednesday. They have since firmed to certain.

The Texas call extends a pattern from election night. Earlier, CBS News projected that Democrats will regain the House, though it said the size of the majority was unclear. The AP also called Republican-held seats in Pennsylvania, Iowa and Wisconsin for Democrats. Early Wednesday, Poliwave's unofficial tracker showed 205 House races called for Democrats and 109 for Republicans, with 121 still uncalled. Those figures alone do not settle whether Republicans finish below 190.

Republicans entered Election Day with 218 House members and one independent who caucuses with them, against 214 Democrats and two vacancies. Before the vote, forecaster Nate Silver's model put Democrats' average projected House gain at 25 seats, which left the 190-seat threshold in question.

The question turns on the size of the Republican total, not on which party controls the chamber. A Democratic majority alone does not decide it. Counting and race calls continue across the remaining districts. Official state results and any runoffs will follow, and independents elected to the House who formally caucus, or announce they will caucus, with Republicans would count toward the Republican total.