Could McCain and other Rs who have signed onto this be thinking that Congress is going to change hands next year?

Maybe they want to change the rules on gerrymandering because they fear Democrats will do what they did when the next census rolls around?

Filed amicus brief w/ @SenWhitehouse calling on #SCOTUS to reassess constitutionality of partisan gerrymandering https://t.co/JOl3cPD4TE

— John McCain (@SenJohnMcCain) September 5, 2017

Senators McCain & Whitehouse file in support of @CampaignLegal’s case to end partisan gerrymandering. Arguments before Supreme Ct in October https://t.co/B56A0aPzBn

— Walter Shaub (@waltshaub) September 5, 2017