It totally depends upon the sport, the team, and the league per sports message boards and politics. I'm a huge NBA fan and my team is in a blue city in a purple state. Both forums I belong to for this team haven't a single Republican, just various degrees of Democrats and sundry liberals, from centrists to far-out leftists who may or may not vote Biden. The local NFL team's forums, are evenly populated by Democrats and Trump supporters, and the battles are non-stop.