Need help on Display Advertising Platform

HI All,

I would want to know the various platforms available for display advertising. I know Adwords, Appnexus etc. But the brand(political party) that I am advertising is not allowed to be advertised in Adwords and Appnexus has a minimum spend restrictions. Can you specify other platforms wherein anyone can register and is not limited to any agency. ALso, I plan to burn around 3 million impressions in a day. It should have a very specific targeting options like state or pin code, device targeting.

Your help would be very much appreciated.

Thanks in advance,