On January 25's edition of the Ezra Klein Show, guest Simon Rosenberg said, "If we run a good campaign, and execute well, I think we're (Biden) going to win this election by high single digits."

I will judge this market by the national popular vote for the presidential race. "High single digits" will mean >7% and <10%. I will use reporting from the Associated Press to determine the margin, and will close this market once the answer is clear (the number of outstanding votes < the margin needed to determine the answer). I will not account for whether Biden runs a good campaign or executes well. The electoral college results will not factor in here, so if Biden wins the popular vote by 8% and somehow still loses the election, this will resolve as Y.