Updated at 9:39 p.m. ET
The U.S. Supreme Court declined to take up a Republican challenge to the newly drawn Pennsylvania congressional map ahead of the 2018 elections.
The decision means Republicans have few, if any, options remaining to try to stem a map that will almost certainly result in Democrats picking up potentially three or four seats and could make half a dozen or more competitive.
Tuesday is the filing deadline for candidates for Pennsylvania's May 15 primaries.