Sometimes stars are caught with their pants down. Literally.

The prize, in the national reporting category, was awarded to veteran reporter David Wood. His 10-part series, “Beyond the Battlefield,” explored the lives of several veterans who were severely injured while serving in Afghanistan and Iraq.

The award may be Wood’s, but Huffington Post cofounder Arianna Huffington is a clear beneficiary. Over the past few years, Huffington has made a point of hiring experienced, well-known and (no doubt) expensive reporters like Wood.

The hirings are part of an effort to position the Huffington Post as a serious news organization — not, as former New York Times executive editor Bill Keller has described it, as an “overaggregator” of “celebrity gossip, adorable kitten videos, posts from unpaid bloggers and news reports from other publications… [with] a left-wing soundtrack.”

The Pulitzer is one small testament to the success of that strategy, and will likely feature prominently in the media kits the Huffington Post‘s sales team sends to potential advertisers.

The Huffington Post is the second online-only news organization to win a Pulitzer, following ProPublica‘s wins in 2010 and 2011. ProPublica partners with many offline publications, however, and focuses on long-form investigations rather than daily news.

Politico, which started as an online-only news organization and has since begun printing a print edition, also won an award this year in the editorial cartooning category.

Jeff Donn of the Associated Press and Jessica Silver-Greenberg of The Wall Street Journal were named runners-up for the national reporting prize.

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