Correct me if Im wrong,
Electors voting for Biden = 222
Electors voting for Trump = 232
Contested states = 84
If a state send both Republican and Democrat delegates, then by law that states electors do not count.
Meaning if PA, WI, AZ and NV have sent both, the tally is
Biden = 259
Trump = 232
270 still needed to win so the electors will get thrown out and it will go to the State Legislatures to vote.