I think it's a more interesting question without the NC Dems. Excluding them, probably Cartwright? If the WAGOP gets its act together though it could be Gluesenkamp Pérez.
MGP is definitely more vulnerable than Cartwright. Much less entrenched incumbent, for starters. Cartwright's district was actually a little over a point bluer in 2020, and it also trended left by more.
MGP seems to have a very good read on the symbolic votes she needs to take to survive, and has branded herself as such I would say. She basically voted the same way Jared Golden does on everything, and we see how well that has worked for him thus far.