California’s “top two” primary chaos, explained

California’s primary elections on June 5 will be one of the most consequential — and bizarre — contests of the entire primary season.

The Golden State is crucial to Democrats’ effort to retake the House — Republicans currently hold a whopping seven districts Hillary Clinton won, and Democrats are eager to pry them away.

The bizarreness, though, stems from California’s extremely unusual “top two” primary system — which pits all candidates of all parties against each other and lets only the first- and second-place finishers move on to the general election.

Often, the top two finishers are one Republican and one Democrat, setting up a normal partisan general election contest. But the top two can also be two candidates from the same party, which would lock in the partisan outcome of a race months in advance.