Wonkette, owned by Gawker Media, became essential reading for many Washingtonians during the 2004 presidential election as Ms Cox posted gossip and commentary on Washington's political class.
She takes up her new post today co-ordinating Time.com's political coverage and writing features and essays for print and web versions of the magazine.
Ms Cox, who also wrote the satirical Washington-based novel Dog Days, joined Time in March as a contributing writer. She will continue to file occasional pieces for the blog.
"You can only write three-sentence posts for so long before you start to crave the comparatively literary world of news magazines," she told Reuters.
"I thought it would be nice to work somewhere that my Mom would not be embarrassed to tell her bridge club about."
Free daily newsletter
If you like our news and feature articles, you can sign up to receive our free daily (Mon-Fri) email newsletter (mobile friendly).
Related articles
- What mainstream media can learn from niche news sites
- 40 essential newsletters every journalist should read
- How Reuters, Newsquest and BBC experiment with generative AI
- From Reuters to The New York Times, Big Oil pays 'most trusted media brands' to push greenwashing
- What do audiences need from climate journalism?
