People generally are not paid to canvass for a candidate unless they are paid staff who decide to pitch in an canvass one day, or work for one of these groups like Acorn, etc.  Except, I thought they had to be non-partisan and stick to issues or voter registration or something, these PACs.  If you are being paid to work on behalf of a candidate, you are a paid member of a campaign staff, or are jumping through some legal PAC loopholes.  Well, that's how it is today, anyway.

The vast majority of people canvassing are volunteers.  I personally know no one who is paid explicitly to canvass.

"Pretending that you already know the answer when you don't is not actually very helpful." ~Migeru.