Take a trip with me to 1932. It's election night and Herbert Hoover received a telegram in the White House which read, "Vote Roosevelt and make it unanimous." In the popular vote FDR won by almost twenty percent. In the electoral college the total was 470 for FDR and 59 for Hoover. Crushing is an understatement. Hoover won the some of the small states of New England and carried Pennsylvania but nothing further west. I mention these things because it is important to remember that Gerrymandering is a scheme to steal close elections and becomes powerless in the face of popular assault. They might can monkey around with a few thousand vote here or there tinkering around the margins, but in the face of a landslide there aren't enough unaccounted for votes to stem the tide.
In the Congressional races the Republicans fared no better. In the house, the Democrats picked up 97 seats giving the them a super majority. In the Senate, the Democrats picked up 12 seats giving them a solid majority and of the contested races that night, Republicans retained only six seats. In the gubernatorial races the Democrats picked up 11 states while the Republicans picked up only Kansas. That night in 1932 changed a lot of things, it meant the Franklin Roosevelt would have a free hand. It also meant that the Republican Party was repudiated and reduced to a fringe Party and reduced to irrelevance.
The Republican Party wouldn't hold power in Congress again for another sixteen years. There's and old adage which goes, every generation votes Democratic once, because it has to. Now is that time we have to. This landslide made Roosevelt's famous 200 days possible with sweeping legislation and sweeping change. The Republicans in Congress could only vote "present" and who cared?