It was fraud.
I can only testify what I have witnessed first hand over the last three years.
I work in an office with many high earners. Well over six figure incomes. Many of these males are life long Republicans. Many grew up in NH. Not transplants from MA, NY(like me) or other more liberal states. Several absolutely hated Trump. They voted for him over Hillary, but did not vote for him over Biden. Several have admitted to leaving that spot BLANK on the ballot 2 years ago.
I counted votes in my town in south central NH last week. My town and my county overwhelmingly voted for the Dem candidate except in the down races. Almost every town in Hillsborough county went for Hassan over Bolduc. We DO NOT have mail in voting in NH. 99% of the ballots in my town were cast last Tuesday in person. I know, I counted the ones that did not get read by the machine. There were less than 25 out of over 1700 ballots.
Bolduc got outspent in the US Senator race 40/1. The Dem ads promoted that Bolduc would take away your SS and keep you from getting an abortion. IT worked. Young and old Independents voted for Hassan. I personally witnessed many ballots that the person voted for Sununu for Governor. Then Hassan and Kuster for Senate and NH2. We LOST in NH.
IF we do not get rid of mail in voting and ballot harvesting we will never win a Nationwide election again.