First, let’s assume that Republicans hold all of their current seats, most notably a competitive open seat in Georgia and embattled Senate Minority Leader Mitch McConnell’s (R) Kentucky seat.

As we’ve been writing for months, the best Republican pickup opportunities in the Senate are in Montana, South Dakota, and West Virginia. The latter two are open seats, and the Big Sky Country seat is held by an incumbent, albeit an appointed one: Sen. John Walsh (D). Let’s give the Republicans these three seats in this hypothetical scenario, which has them flipping two seats where the incumbent is retiring and one where the incumbent is running. That’s one incumbent defeat and a net gain of three seats so far, halfway to the six needed to win the majority.

The next four most vulnerable seats are held by incumbent Democrats in Alaska, Arkansas, Louisiana, and North Carolina, all Toss-up races. Remember, under this scenario, Republicans have to take the Senate and only beat two incumbents. So let’s say that Republicans only manage to beat one of these four incumbents: Sen. Mark Pryor (D-AR).