EXTON, Pennsylvania (AP) — For many voters in America's affluent suburbs, a flourishing economy is forcing a thorny dilemma for the midterm elections.

Do they vote Democratic, in part to protest President Donald Trump for behavior some see as divisive and unpresidential? Or do they back Republicans in hopes that the economy will continue thriving under the majority party?

A healthy economy has at least complicated their decision and blurred the outcome of the midterm elections . On Friday, the government reported that employers added a robust 250,000 jobs in October. And the unemployment rate...