All it takes is one state to declare an election fraudulent and all 49 other states are automatically done so, as I understand it. If you have fraud in one state, then it can be in the others.

Arizona declares election fraudulent. https://www.azleg.gov/legtext/55leg/2R/bills/HCR2033P.htm

the State of Arizona that it is the justifiable position of the Arizona State Legislature that we set aside the results of the Maricopa, Pima and Yuma County elections as irredeemably compromised and reclaim the 2020 Presidential Electors due to the irredeemably flawed nature of these elections that prevent the declaration of a clear winner of said presidential electors.