2 House Races in Ohio Will Test Democratic Divisions and Trump’s Sway

In the Cleveland area, a bitter primary election is pitting the left against the Democratic establishment. Near Columbus, a Trump-endorsed candidate faces a crowded Republican field.

Two primary contests on Tuesday for open House seats in Ohio are poised to act as a stress test for both Democrats and Republicans, offering early hints about whether party leaders are aligned with their voters ahead of the midterm elections next year. In the Cleveland area, two Democrats are locked in an increasingly embittered and expensive clash that has become a flash point in the larger struggle between the party’s activist left flank and its leadership in Washington. The early favorite to win, Nina Turner, is now trying to hold back Shontel Brown, the preferred candidate of more establishment-friendly politicians and allied outside groups. Ms. Turner, a former state senator who built a national following as a surrogate for Senator Bernie Sanders’s presidential campaigns, has been buoyed by support from Representative Alexandria Ocasio-Cortez of New York and other leaders in the progressive movement. But Ms. Brown, a local Democratic Party official, has benefited from the help of Hillary Clinton, Representative James E. Clyburn of South Carolina and others in party leadership roles.