On June 11, the Commission on the Practice of Democratic Citizenship, a unit of the American Academy of Arts and Sciences, released “Our Common Purpose”, which recommends various election law changes. Here is the 84-page report.
Recommendation 1.1 is to substantially enlarge the size of the U.S. House. Recommendation 1.2 is to implement ranked choice voting in presidential, congressional, and state elections.
Recommendation 1.3 is to repeal the 1967 federal law that requires states with more than one member of the U.S. House to have single-member districts.
Combining all three recommendations would enable the nation to use proportional representation, specially Multi-Winner Ranked-Choice Voting.
A larger U.S. House would also have the side benefit of making the electoral college work better than it does now. It would reduce the disproportionate power of very small-population states. Also in case the U.S. House were ever called on to choose a president, the results would be less subject to gerrymandered U.S. House districts. Thanks to Fairvote for the link.