That doesn't necessarily mean the base price will be that. I'm betting that the $71,860 is the allowable price that GM will allow to give away that car. Doesn't mean it will be a "base" model but the actual retail value is to not exceed $71,860.
Anything over that would be covered by the winner.
"A 2014 Chevrolet Corvette Stingray. Approximate Retail Value ("ARV"): $71,860.
Administrator will determine all features of vehicle including but not limited to color
of exterior and interior, and all other features or upgrades will be allowed only if
permitted by delivery dealer and paid for by winner"