There’s an adage that advises against mixing friends and money… but it must have been formulated before a presidential candidate could gain hundreds of thousands of virtual friends on the web, each with their own credit card.

The New York Times reported this week that Democratic presidential candidates have had more success than their Republican counterparts in channeling the infinite resources of the internet into their coffers, largely thanks to aggressive campaigning on social-networking sites.

Nearly all the candidates boast profile pages on Facebook or MySpace, the two most-popular networking sites and two of the most popular sites on the web. Facebook this month reported 30 million members worldwide and the number of MySpace users is at least double that amount.

Obama, who according to the Times is one of the leaders in online fundraising, has made more than 100,000 Facebook friends. His page boosts his image as the hipster candidatepartly by listing interests such as his favorite TV show: ESPN’s “Sportscenter.” Giuliani, who is lagging in online fundraising, has gone for a less friend-friendly approach, opting out of Facebook altogether and using a “private” MySpace page that welcomes only pre-approved friends. Why be choosy? When it comes to raising money, being an online-friend whore pays!

John Edwards, who the Times reports logs on to twenty-three social networking sites, has supplemented his profiles with casual punch e-mails, encouraging cyber-supporters by the hundreds of thousands to join the campaign.

The social-networking-site campaigns could quickly turn into a popularity contest better suited to a high school cafeteria. They’ve also already become another measure by which the mainstream press can frame the campaign as horse race long before people should be taking bets. Meantime, it’s an encouraging sign that politicians (or their advisers) are realizing that young people’s lack of interest in CSPAN and the nightly news doesn’t equal a lack of interest in politics. On the contrary, a lot of our phones and our laptops are synched to the newswires.