LORELAI: He’s a ringer.
RORY: How do you figure?
LORELAI: Someone recruited him, promised him a handsome sum, financed his theatrical snowman accoutrements, so he could snatch victory away from a deserving local in order to bag the contest prize for himself.
Ringer is slang for a contestant who enters a competition under false pretences, such as a professional entering an amateur contest. It comes from horse racing, where a fast horse was sometimes substituted for a slower one, known as a “ring-in”.
Although Lorelai is being deliberately preposterous, it does seem a little mean for such an experienced competitor to enter a local contest in a small town, especially when there isn’t even a large prize to act as an incentive. He isn’t actually building a snowman anyway – he’s creating an ice/snow sculpture, which is a different entity. I feel as if he should be disqualified.