Smithsonian.com

If you got emails like “Hey,” and “Wow” and “Join me for dinner?” from Barack Obama this campaign season, you were the recipient of some finely tuned pieces of advertising. Obama’s team tested as many as 18 variations of each email before they sent them out to their millions of subscribers, and that testing worked. According to Businessweek, most of the $690 million the Obama campaign money raised online came from those emails.

What worked might surprise you. Ugly emails did well. Constant bombardment of emails worked. So did cursing. Emails with that simple “Hey”  subject line were actually the most successful of all. Businessweek writes:

It quickly became clear that a casual tone was usually most effective. “The subject lines that worked best were things you might see in your in-box from other people,” Fallsgraff said. “‘Hey’ was probably the best one we had over the duration.”

Another blockbuster in June simply read, “I will be outspent.” According to testing data shared with Bloomberg Businessweek, that message outperformed 17 other variants and raised more than $2.6 million.

And pretty didn’t work at all. In fact, uglier emails did way better.

“We were so bad at predicting what would win that it only reinforced the need to constantly keep testing,” Showalter said. “Every time something really ugly won, it would shock me: giant-size fonts for links, plain-text links vs. pretty ‘Donate’ buttons. Eventually we got to thinking, ‘How could we make things even less attractive?’ That’s how we arrived at the ugly yellow highlighting on the sections we wanted to draw people’s eye to.”

So don’t expect donation emails to be getting any prettier or more classy. Because the data shows that you’ll keep on giving.

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