There s so much diversity in the Democrat presidential candidate pool, it must be hard for these  celebrities  to choose who they re going to throw their money and support behind..Katy Perry is publicly showing her support for Hillary Clinton.The pop singer, in her first appearance for the 2016 campaign, will rally Clinton supporters on Oct. 24 in downtown Des Moines before the presidential nominee attends the Iowa Democratic Party s annual Jefferson-Jackson Dinner, Clinton s campaign announced Saturday morning.Perry had a hand in rallying supporters for President Barack Obama when he was a candidate by performing at numerous events and wearing patriotic outfits she designed herself, including a dress she wore to a rally that displayed his campaign slogan  Forward  and a ballot dress she sported at a Las Vegas rally.She was a key part of the Obama campaign s strategy to get members of various communities to attend events. Campaign volunteers would sign up attendees to vote and even offer to take them to voting locations if they needed transportation.The Hollywood Reporter exclusively announced Friday that Christina Aguilera and her producer-fiance Matthew Rutler will host Clinton s last big fundraiser of the year on Nov. 4.The Des Moines event is free and open to the public, and registration is encouraged.Christina Aguilera and her producer fianc  Matthew Rutler will host Hillary Clinton s last big fundraiser of the year at their Los Angeles house on Nov. 4, sources tell The Hollywood Reporter.Clinton s trip falls shortly after her Oct. 26 birthday and is expected to draw a large celebrity crowd. Her last event was held at Lionsgate s Rob Friedman s home; the Nov. 4 fundraiser is expected to be a sold-out event.The final fundraiser is being put together by Clinton s Hollywood bundlers, including CAA s Darnell Strom and Michael Kives.On Nov. 5, Michelle and Rob Reiner, Cynthia Telles and Joe Waz will hold a discussion with Clinton from 12 p.m. to 2 p.m. The event,  Conversation With Hillary,  will allow attendees to make contributions ranging from $1,000-$2,700.After announcing her candidacy in April, she has made monthly trips to Los Angeles, where she has raised tens of thousands in Hollywood contributions.A-listers including Kanye West, Kim Kardashian, Tom Hanks and wife Rita Wilson, Usher, Jessica Alba, Jeffrey Katzenberg and more previously gathered this past August to support Clinton at the house of talent manager Scooter Braun, who boasts a large list of young talent including Justin Bieber and Ariana Grande. Kardashian and West even took a selfie with the presidential candidate after hearing her goals for the country, where she defended Planned Parenthood and supported President Barack Obama s environmental initiatives.