Your memory is a bit off. :)
You see, the Yank Kickstarter campaign was at 65% on campaign day #25, 12 days before the end of the campaign. In those last 12 days, $12,592 was raised from 161 different people for an average of just $78 per person which is actually considerably less than the average backer of about $96 throughout the campaign.
The big ticket backers appear to have contributed more in the middle of the campaign. What happened in the last few days is pretty normal for a successful Kickstarter campaign when people who have been watching finally decide to back it and spread the word to even more people just before the end of campaign.
Data from Kicktraq