Damn, almost had you.
But seriously. Do you have any outstanding warrants? LOL I'm serious, they often draw in people with outstanding warrants with free giveaways.
The key is this: If you don't remember entering into a contest, then it probably isn't genuine.
Do NOT EVER give anyone your personal banking information, social security number, or other personal information. If you don't remember entering into a contest with a free lawn tractor, then odds are this is a scam. Ignore em if they want you to pay "Sales tax" on the item, or some other charge like shipping and handling. This will be a scam.