Jenkins seems to be voting a Verified -1 for aborted jobs. They should only touch their particular flag or not vote at all for aborted. Example: http://review.gluster.org/#/c/14973/
We had a "failed" vote for default gerrit trigger as -1 verified and -1 code review. This is most likely what caused it. I've set it to 0. Will re-open if we see this again.