Several Democratic-controlled state legislatures are working on laws to require presidential candidates to file copies of their tax returns with the state to qualify for the ballot, a move directly aimed at Trump, who has refused to disclose his income tax forms. The Supreme Court has already struck down state-legislated term limits on senators and congressmen. In U.S. Terms Limits Inc. v. Thornton, Justice John Paul Stevens wrote, “If the qualifications set forth in the text of the Constitution are to be changed, that text must be amended.” Presumably, that obstacle with states meddling in congressional qualifications would also apply to presidential standards. However, Laurence Tribe, a Harvard University law professor, said the tax filing requirement is “not an interference with any federal prerogative, nor does it filter out in advance any set of presidential candidates who meet the Constitution’s age, residence, and other qualifications.” Source: https://newrepublic.com/article/147310/can-states-ban-trump-ballot-doesnt-release-tax-returns The general assumption is that Republicans would challenge such laws soon after they are enacted or enforced. However, a cleverer approach might be to hold off on the legal appeals until soon after the 2020 election. If Trump, disqualified in several blue states, loses the electoral college vote, Trump’s attorneys could ask the Supreme Court to declare the tax filing requirement unconstitutional, which must be remedied by tossing out the electoral votes in all the states that denied voters their constitutional right to vote for Trump. If the conservative-majority court agreed, Trump would likely have most of the remaining electoral votes and be reelected president.