A spokeswoman told the New York Times on Thursday that Sebelius "is continuing her important work at H.H.S. and is not considering a run for the Senate."
Democrats were reportedly courting Sebelius to challenge Republican Sen. Pat Roberts this year in Kansas, the state where she served as governor before joining the Obama administration, and she was said to be considering a run.
Although she won two terms as governor and Roberts is considered vulnerable, Sebelius would have likely faced a tough race. A survey from Democratic firm PPP earlier this year found that 55 percent of Kansas voters have an unfavorable opinion of Sebelius. The poll also showed Sebelius trailing by 14 points in a hypothetical matchup against Roberts.
Moreover, the state hasn't elected a Democrat to the Senate since 1939.
This post has been updated.