Democrat Optimism in Six Senate Races May Be a Mirage—What the Polls Reveal

Democrats are optimistic about their chances of flipping the Senate in the midterm elections following a string of favorable polls. But history offers a warning to Democrats, as polls in recent elections underestimated Republicans in key states. Control of the Senate could come down to just a handful of races where polls show razor-thin margins. Alaska, Iowa, Maine, Michigan, Ohio and Texas have emerged as the most competitive races where both parties are hopeful about their chances. Recent polling points to tight races in each of those states. But Republicans have outperformed polling averages in many of those same states...