Nate Cohn for the NYT:

The next phase of the redistricting war is starting to come into focus.

Indiana, Missouri, Ohio and perhaps Florida — all Republican-controlled states — seem likely to join Texas and California in attempting to redraw their congressional maps, according to my New York Times colleagues. By their tally, Republicans could carve out up to seven more House seats where they would be favored to win.

It’s too soon to be sure if these states will follow through, let alone whether it would mark the end of this cycle’s redistricting battles. Other states could join; a legal challenge to Utah’s map and a challenge to Section 2 of the Voting Rights Act also loom. But suppose that this is where the redistricting war goes next, and where it ends. If so, how much would the new maps tilt the playing field toward Republicans?

Ultimately, the most important question is whether redistricting prevents the party that wins the national popular vote from winning control of the House. If the popular vote winner is still likely to prevail, then gerrymandering, however odious, hasn’t necessarily left one party at an undemocratic disadvantage overall.

By this measure, the House map was fundamentally fair in 2024: Despite plenty of gerrymandering, the winner of the popular vote was reasonably likely to win the most seats. But if the new maps are enacted in all of these states, Democrats will need to win the national popular vote by two or three percentage points to be favored to retake the House, according to projections based on recent congressional and presidential election results.

A two-to-three-point structural advantage for the G.O.P. is meaningful, but pretty modest. With Democrats leading by four points in the national generic ballot polls today, the party would still be favored to win next year’s midterm election. The Republicans wouldn’t stand much of any chance at all of surviving a so-called “wave” election, like in 2018, when Democrats won the House popular vote by seven points.

But while Democrats would be favored if the election were held tomorrow, the race for the House would be significantly more competitive on the new maps. Even if the Democrats won, the likeliest outcome would be a piecemeal seat-by-seat battle in which control of the chamber would come down to a fairly small number of seats. The race might not be called for days. Democrats wouldn’t have much margin for error: A few mediocre Democratic recruits, some ill-timed retirements, an unexpected demographic shift or even plain bad luck in contests with razor-thin margins could be enough to give Republicans control even if the G.O.P. loses the popular vote by a modest margin….