I wouldn't be so sure about that.
My wife gave me this book for my birthday. https://www.amazon.com/Ratf-ked-Behind-Americas-Democracy/dp/1631491628
I haven't finished it yet, but the premises is that in 2009, the Republicans knew the 2010 census was coming up. In a lot of states, if after the census comes out, if it changes the number of House Seats, then they redistrict. Redistricting in most (not all) states is done by the majority party in the state legislature. The Governor has veto power.
I suspect you can see where this is going. Rs concentrated on state houses and Governor races. Using Big Data and map software, They put the Ds in Gerry mandered districts and Gerry mandered the rest for them or making it close that they could influence by funneling in big money.
It worked and the districts are still in effect for 2018.
Should be an I interesting election.