Campaign web site software is often poorly written. If you enter a negative number in the amount field you can usually transfer from money FROM the campaign TO your bank account.

Okay, not really. It's probably a refund. Not sure what the exact specifics of the transaction are. We get our data from OpenSecrets.org and they list the same negative contributions on their site.

http://transparencydata.com/filter/#Y3ljbGU9MjAwNiZjb250cmli...

http://www.opensecrets.org/indivs/search.php?name=garber,+do...