Was the Powell Case ruling the reason Harry Reid had to seat Burris?

I think that the only thing that would keep Burris out, or later cost him this position is related to pay for play. We do know that Burris donated over $20,000.00 to Blago's recent campaign and that afterwards, Blago granted over 70,000.00 in government contracts to Burris' public relations consulting firm. It doesn't look good.