I expect that the polls will turn out to be wrong—but I do not know in which direction. Politics has changed enough in the past two years so that rules for predicting outcomes based on past experience, such as those for identifying likely voters, can no longer be trusted. If the polls are wrong in one direction, the Republicans hold the House and increase their majority in the Senate. If they are wrong in the other direction, they lose the house by a substantial margin, probably lose the Senate as well. We will have to wait and see.
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