This is the "You've Won a Free Trip" scam. Just give them your credit card number for "incidental expenses", they'll bill the [***] out of it, and you can go on your $8,500.00 "free" trip.
Caller Id display indicates only "Michigan Caller". Didn't answer, so I don't know what the call was about. I get a lot of "Michigan Caller" calls these days. Figure a lot of them, if not all, are political in nature, but don't know for sure.