The US midterm election is not until November, but the selection of candidates is already well under way. Democrats have been encouraged by a host of recent election victories, but President Trump is a formidable opponent. If Democrats gain control of a chamber in the federal Congress, the legislative side of the Trump presidency is basically over. While most focus will be on the national races, the results in thousands of state and local races are important for policy and politics alike. And the 2020 presidential election is already framing the political debate.