During Obama's 2007 presidential campaign, his team hired Dan Siroker from Google to help with online marketing. Siroker tested different button colors, images, and wording through A/B testing and found variations that increased signups by up to 40%. As a result, around 4 million of the campaign's 13 million email addresses and $75 million in donations came from this testing. The document discusses how A/B testing and marketing automation platforms can now track "digital body language" like website visits and clicks to better target prospects. It claims that classic marketers must embrace these new digital techniques or become irrelevant.