In most of the country, the real choice for a seat in Congress or the state legislature is made in the party primary, not in November. When a district reliably favors one party, the winner of that party’s primary is almost certain to win the seat.
Few people vote in primaries. The Bipartisan Policy Center found that 21.3% of eligible voters cast a ballot in the 2022 primaries, which means nearly 80% of eligible voters did not take part in the step that decided most seats.
The people who do vote in primaries tend to be the most engaged members of each party. A member of Congress in a safe seat therefore has more reason to worry about a challenge from within their own party than about losing to the other one, and that shapes how they vote and what they say.
Rules differ by state
Some states hold closed primaries (only party members vote), some open (any voter picks a party’s ballot), and a few use a top-two or top-four primary in which all candidates appear on one ballot. Your state’s election office explains which applies to you.
States have tried different designs to widen participation, from open primaries to ranked-choice voting. Supporters and critics disagree about how much each changes the candidates who win; the evidence is still being studied.
Before your next primary, check whether your state’s primary is open or closed, and whether you need to register with a party by a deadline to take part.