What heppens when...

From the FAQ: You must redeem the game on the account you entered with, and may not trade it to others.

In short, you'd be screwing the person who created the giveaway. They'd have to re-roll (if you told them) and if you didn't tell them you'd probly get banned. In other words, don't be an idiot or a d-bag. You don't need two copies of the same game. It's common sense and common courtesy.

That's selfish bro. Remove your entry and redeem your key. It's the right thing to do.