The polls I have seen indicate that support for free trade among Democrats has increased over the last few years. There are undoubtedly two reasons for that: the negative economic impacts of Trump’s tariffs; and the general toxicity of his brand in the eyes of everyone outside his base. And yet, none of the Democratic candidates is running as a free trader in Iowa, a state which naturally leans against protectionism. Why?
Because the candidates know that the general election will almost certainly be won in the Rust Belt, and Rust Belt voters generally support measures to protect their declining industries. Promoting free trade will win you more votes in places like California and Washington, but running up huge margins in those states won’t help you get elected. So, blame the Electoral College for forcing the candidates to emphasize the agendas of swing voters over the interests of the country as a whole.