re: Can gambling losses be deducted from 1099-MISC?

You do not have to claim the full MSRP on your winnings. If you can document that you could have (or did) gotten the prize for a lot less, you need only claim that amount. So, if you won a car with an MSRP of $25K, but you can get a statement from a dealer that they sold that same car with the same options for $21K, that's all you need to claim.

You really should get contemporaneous documentation, however, as claiming something less than what is shown on the 1099 just might invite an audit. However, if you don't want to risk an audit (because you may have other "iffy" items on your return), there is a method by which you can call the IRS and file a Form 4598 to get the prize company to issue a corrected 1099.

As far as deducting losses, you're out of luck. The IRS takes the position that sweepstakes type winning (where you don't really have to do anything but enter -- i.e., you're not putting up any of your money to get a chance to "win") are not considered "gambling winnings" and therefore cannot be offset by gambling losses.