Singer Katy Perry stands on stage during a rally for Hillary Clinton, former Secretary of State and 2016 Democratic presidential candidate, not pictured, ahead of the Jefferson-Jackson Dinner in Des Moines, Iowa, U.S., on Saturday, Oct. 24, 2015. Clinton's odds of winning the Democratic presidential nomination are now at or near an all-time high, according to prediction markets PredictWise, Pivit, and PredictIt. Photographer: Daniel Acker/Bloomberg via Getty Images
