Time magazine's Michael Scherer talked with a group of Obama campaign advisers this past weekend, and provided an inside look at some of the data and targeting tactics behind the president's re-election. The article touches on many different aspects of the campaign's data operation, from television advertising to campaign insiders' wagers about which email subject lines would be most successful.

Among the insights: The campaign made a special effort to win back voters who had taken themselves off of the campaign's email list.

"People who had unsubscribed from the 2008 campaign email lists were top targets, among the easiest to pull back into the fold with some personal attention," Scherer reported.

The campaign's enormous demographic databases also helped determine the ideal Hollywood celebrities to host a series of dinners with Obama — a key part of the campaign's fundraising efforts. When the campaign offered donors a chance to win dinner with film star George Clooney and the president, the contest raised "millions of dollars." The people most likely to respond and donate, the campaign discovered, were "West Coast females ages 40 to 49."

So the campaign looked for another celebrity on the East Coast who would appeal to that same demographic of women. A campaign adviser told Scherer that there were plenty of options. But the East Coast equivalent of George Clooney that they chose was Sarah Jessica Parker.

According to ProPublica's analysis, the campaign's microtargeting may not have ended there. As we reported in June, the Obama campaign's emails advertising dinner with Sarah Jessica Parker actually came in several variations.

Some members of Obama's email list received invitations focused on the Sex and the City star herself. Others received an email highlighting the fact that Vogue editor Anna Wintour would be present at the dinner. A third group were told that pop singer Mariah Carey would be giving a private concert afterwards. It's not clear whether the campaign was using these other celebrities to attract the same demographic group of women 40 to 49, or whether they were trying to appeal to slightly different audiences.

Both the Obama and Romney campaigns have declined to speak about almost any aspect of their targeting tactics until now. We'll be continuing to look at how campaigns used voter data this cycle, and how targeting will affect elections from now on.