Well....I'll give you the New Jersey gubernatorial race.   However.....
1) All of the special elections that Dems have lost since the 2016 Election have been GOP strongholds, and yet Trumpies have said that was an indication of Dem failure.
2) I wouldn't call Virginia a historic stronghold, but I don't think it's too far off from becoming one.  A 25-year House of Delegates incumbent that has acted as nothing short of a big league homophobe and "bathroom bill" sponsor, just got his clock cleaned by a transgender candidate.  The House of Delegates is going from a 66-34 GOP majority to a 52-48 majority.