A candidate who is aggrieved has one key focus point after the counting stops.
You must sue to stop the certification. Every state is a bit different, but broadly once the certification is done it is extremely difficult to overturn an election even if there is evidence of cheating.
The rule of law matters.
#patriotgames
Everyone thought it was cool to take selfies doing crimes until the FBI got all their data from Google and said hello.
https://www.vox.com/recode/22867000/january-6-fbi-search-facebook-google-insurrection