From John Curiel, at Real Clear Politics:

What can be done about redistricting? Unfortunately, with moderate Sens. Joe Manchin and Kyrsten Sinema protecting the Senate filibuster, not much at the national level. Likewise, Republicans have no reason to give up their power in states such as Wisconsin and North Carolina where they control redistricting.

A possible national-level solution more amenable to Republicans might be to increase the size of the House, which has been capped at 435 members since 1913. Political scientists Francis Lee and Bruce Oppenheimer suggest that increasing the House at a ratio followed by other Western democracies – the cube-root rule – would lessen state legislatures’ ability to manipulate district boundaries. Such a change would increase the size of the House to over 544 members and would need only legislation, as opposed to a constitutional amendment, to implement. Republicans would presumably have no reason to go along with such legislation, however, if they did not see it as advantageous to them; and Democratic representatives might likewise not enjoy the loss of their individual power. With more representatives, the power of any single representative diminishes. Additionally, increased chamber size would increase the power of party leaders, which could further nationalize politics.

A less aggressive approach might be to encourage states to redistrict in a manner – such as not splitting ZIP codes and similar geographies – that preserves the ability of constituents to communicate with their representatives. Redistricting in a manner where representatives could more easily figure out whom they represent could allow for some dimension other than party to play a role in elections, empowering individual candidates. Likewise, such districts could lower the cost of campaigning and allow for more responsiveness. The Republican National Committee professed a deep concern over communities of interest and existing boundaries in their amicus brief for Gill v. Whitford, which ended redistricting litigation at the national level. Even if Republicans came on board for such a scheme, though, such effects would be marginal and pale in comparison to the overwhelming effect of partisanship on the opinions and actions of representatives. Likewise, such reforms to preserve boundaries don’t answer the question as to how the Senate became so polarized even in the absence of gerrymandering.