ALBANY,Indexbit N.Y. (AP) — Democrats in charge of New York’s Legislature have proposed new lines for congressional districts that could give them a potential boost in the key battleground state hours after rejecting boundaries created by a bipartisan redistricting commission.

The legislation proposed after Monday’s rejection vote leaves much of the Independent Redistricting Commission’s recently unveiled map in place, but it includes changes to districts in suburban Long Island and the Hudson Valley north of New York City.

The Democratic proposal is a significant step in the yearslong battle over New York’s 26 congressional seats, since even slight tweaks in the state’s map could help determine which party controls the U.S. House after the November elections. Republicans have already threatened a legal challenge if the lines are approved.

The legislation could be voted on this week.

The state commission’s map would have helped Democrats in two districts and Republican Rep. Marc Molinaro in another, but it left most of the current lines in place.

New York Law School professor Jeffrey Wice, who focuses on redistricting, said “this new map doesn’t veer that far off from the commission’s map.”

But he noted the lawmakers’ proposal would make changes to the Hudson Valley district held by Molinaro that could make his race more competitive.

The proposed map also would slightly reconfigure three districts on suburban Long Island, including the seat won recently by Democrat Tom Suozzi in a special election. That district was formerly held by George Santos, who was expelled from Congress.

Wice said the Legislature’s proposed map could help Suozzi, as well as Republican Rep. Andrew Garbarino.

The Independent Redistricting Commission was supposed to draw the districts used in 2022, but it failed to reach a consensus. Democrats who control the Legislature then drew their own map, which was intended to give Democrats an edge by stuffing Republicans into a few super districts to dilute GOP voting power across the state. A lawsuit eventually stopped the Democrats’ map from being used, and a legal challenge delayed the congressional primaries.

The state’s highest court then appointed an outside expert to come up with a map for 2022. Republicans performed well under those congressional lines, flipping seats in the New York City suburbs and winning a narrow House majority.

After the defeats, Democrats sued to throw out the 2022 map. The case eventually reached the state’s high court, which in December ordered a new map to be drawn in a ruling that said the commission should have another chance to craft district lines.