If you have a war chest of $16 billion to throw at TV and print advertising, you don’t need to mess around with piddly little banner ads, right? Well, while Mayor Bloomberg did indeed blitz New Yorkers with print mailers and TV ads, he didn’t exactly ignore the digital front. His campaign spent at least $2.1 million on online ads, or about 2.5 percent of the $85 million he has disclosed he put into the mayoral race.

He’s no Barack Obama—the president spent about 3.5 percent of the $744 million he raised on internet media, according to OpenSecrets.org—but it’s a perfectly respectable showing.