Cohen said in a new reaction video that McMaster's call for a special session presents a "do or die" scenario for blue states that could help thwart Republican gains through gerrymandering.

"The onus is now on us to apply as much pressure as humanly possible to our blue state officials," Cohen said. "And if they won't do it, like Maryland State Senate President Bill Ferguson, then we need to support Bobby LaPin, his primary opponent, who's running against him. If they won't do it, like Colorado Gov. Jared Polis, then we need to support the gubernatorial candidates in Colorado who will."

The push for South Carolina to adopt a new election map came after the Supreme Court ruled in Louisiana v. Callais that states can gerrymander their maps for partisan purposes. Already, red states like Florida, Louisiana, and Alabama have redrawn their maps to eliminate Democratic congressional seats.