What happens if, as seems much more likely now than it did a year or six months ago, Democrats overturn the Republican majority in the Senate?

No clear answer yet, but Democratic senators have reportedly set up a “war room” to enable them to abolish the filibuster and quickly pass a Biden-Harris agenda. Other Democrats have urged that a Democratic Congress admit new states to the union, each with two senators, up to a dozen, with a view to blocking a Republican majority forever.