"House Republicans and Democrats don't agree on much, but both believe control of the chamber is in play in this fall's election, with energy and the environment likely factors in several competitive races.
Kyle Kondik, an analyst at the University of Virginia Center for Politics, said policy issues are not usually the determining issue in midterm elections. He said that often the popularity of the president — especially one like Donald Trump, who has had a negative approval rating for much of his term — decides contests in nonpresidential election years.
Indeed, House Democrats have seized on President Trump's low ratings and are targeting GOP incumbents in districts carried by Hillary Clinton in 2016. They believe that if the election is a referendum on Trump, they'll come out winners."