Fred Wellman, host of the progressive podcast On Democracy, defeated longtime incumbent Republican Ann Wagner

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Fred Wellman’s victory in Missouri’s second congressional district on Tuesday was such a surprise that NBC News’s star data analyst Steve Kornacki didn’t even have a graphic prepared, he told supporters on election night.

Longtime Republican incumbent Ann Wagner, who had been widely expected to hold her seat, was swept aside as part of a broader wave of Democratic victories across the country.