USA Senate in 2020:
It is an uphill battle for the Republicans, the way I see it. 23 Republican seats vs 12 Democrat seats are up for grabs.
The Republicans need to win 2/3rds of the battles just to remain even and 60% of the battles to keep the senate.
If the Democrats win just half the seats that are up for grabs, they would flip the senate. With their 2 independents that usually vote for Democrats, they would have a comfortable majority.