House Republicans struggling to preserve their majority are facing a wave of Democratic money and enthusiasm in suburban districts across the country, as well-educated and moderate voters consider new checks on President Trump.
An analysis of the types of districts in play shows that two-thirds of the Republican-held seats that a top election handicapper sees as vulnerable are in suburban areas.
That has Republicans on defense in an area where Trump has bled support, even in the 2016 election he won.
The Cook Political Report lists 64 Republican-held seats as either pure toss-ups, or leaning slightly toward Democrats or Republicans.
Of those districts, 42 are classified as suburban by the researchers David Montgomery and Richard Florida at CityLab.