Democrats are dying to have Sebelius enter the Senate race in Kansas.
Warner is the first Democrat in five years to headline the annual Shad Planking event.
Warren has said she is not running in 2016.
The Texas senator threw his support to Oklahoma Senate candidate T.W. Shannon.
Multiple controversies have jolted the Kansas Senate race.
Idaho House challenger Bryan Smith (R) released a new television ad Wednesday defending his career as a trial lawyer after a series of attacks.
The ad, titled “Guardian Angel,” features former client Shelli Long Kendrick praising Smith for suing her insurance company after it tried to avoid covering her cancer diagnosis when she was 13.
Ed Gillespie said Sen. Mark Warner (D-Va.) isn't the centrist he claims to be.
Friends and former colleagues are skeptical that she'll jump back into politics.
Illinois's Republican and Democratic senators have an unusually close relationship.
Oregon GOP Senate candidate Monica Wehby announced her first TV ad Wednesday.