(CNN) House Democrats have been very careful in the opening days of Congress to pick their fights carefully.

Led by House Speaker Nancy Pelosi (California), the party stood up to President Donald Trump over his demands for a border wall -- and won. But even with that victory in hand, top Democratic strategists are wary not to overstep their mandate from the 2018 election -- concerned that looking as though they are attacking Trump on all fronts at all times will a) lessen the impact of any one fight and b) create a toxic partisan environment that could hurt them and their eventual 2020 nominee.

new Washington Post/ABC News poll seems to suggest a clear next fight for Democrats to pick: a legislative attempt to force Trump to release at least some of his past tax returns.

Six in 10 said House Democrats should seek "to obtain and release Trump's tax returns." Just 35% of those polled said Democrats should not exert legislative powers to get their hands on Trump's tax returns.

Beyond those topline numbers, the energy is all on the side of the House working to get the returns; 46% of people who said Democrats should try to get them felt that way strongly, as opposed to 26% who felt strongly that Democrats shouldn't try to obtain the returns.

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