From Media Post Online Spin:

“If you have been following what these candidates have been raising, you know it’s certainly not an issue of money. But there is a fair amount of blame that falls on the ad networks and online media properties not making it easier to buy. While brands have time to test and learn, campaigns are in very compressed time cycles. Contextual and behavioral ad networks need to make it easy for them. Candidates have certainly learned how to pull money out of online interactions. Now if they could only figure out how to get a return on putting money back into online.” (Read More)