Blue wave? Not so fast. Midterm elections may be more map than mood
The conventional wisdom of midterm elections rests on a basic premise: the political environment determines the outcome. When voters are unhappy with the economy or frustrated with the party in power, they punish the president’s party at the ballot box.

TL;DR
- Midterm election outcomes are determined by the political environment.
- Voters punish the president's party when unhappy with the economy.
- Voter frustration with the party in power leads to electoral punishment.