Curtis is more of an Akin than Gianforte, and neither come even close to being an Akin. A Curtis vs. Gianforte race would be Leans R at best for Ds, and that's being generous to them. If Ds are smart, they'll nominate Quist.
I won't disagree on that last point, but I always have to give the side-eye to candidates as far-right as Gianforte, knowing the tendencies of those esteemed far-righties who came before him (Akin, Mourdock, Angle, et al).
That being said, I'm no Montanan, so maybe I'm talking out my ass.