The GinsBORG
>If there were no winner of the presidential election by Jan. 20, the Constitution dictates that the Speaker of the House - currently Democrat Nancy Pelosi - would become acting president until a successor was confirmed.
''Not necessarily.''
Pelosi has to win 2, count them 2, elections. Her House seat and the Speaker seat.
The House (all of them) and Senate (1/3rd of them are sworn in on the 4th of January.
Then the House selects the Speaker, the Minority Whip and the Majority Whip.
Who takes the House, D's or R's, then Who becomes the Speaker will determine the progression if there is no definite winner declared by then.
Could be several different outcomes.
doc 1 - House Floor Rules. from 2018
doc 2 - Senate Floor Rules. from 2018
Haven't found the 2020 doc's, may not be out yet.