Obama moved up the list compared to 2012, while Clinton moved down.
Last year, Clinton was No. 2 while Obama was No. 7.
Leading the list was Angela Merkel, the chancellor of Germany, who was also No. 1 in 2012.
Merkel has "made the list eight times out of the past 10 years — seven times as No. 1," according to Forbes.
Other American politicians on the list include Homeland Security Secretary Janet Napolitano at No. 8, House Minority Leader Nancy Pelosi (D-Calif.) at No. 22, and Health and Human Services Secretary Kathleen SebeliusKathleen SebeliusLeaked email: Podesta pushed Tom Steyer for Obama’s Cabinet Romney: Trump victory 'very possible' Fighting for assisted living facilities MORE at No. 25.
Other notable American women included: Melinda Gates, who came in third; Facebook Chief Operating Officer Sheryl Sandberg, who came in sixth; Oprah Winfrey, at No. 13; Beyonce Knowles, at No. 17; New York Times Executive Editor Jill Abramson was No. 19; and Angelina Jolie came in at No. 37.
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