President Obama turned a planned campaign speech in Fort Myers, Fla., into a brief statement about the shooting rampage. He asked the audience to join him in a moment of silence for the victims. Mandel Ngan/AFP/Getty Images hide caption

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Sen. Marco Rubio, R-Fla., delivers a speech during the annual Conservative Political Action Conference in February in Washington. Win McNamee/Getty Images hide caption

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Newt Gingrich greets supporters during a campaign appearance at a restaurant in Reno, Nev., on Wednesday. He said Thursday he will challenge Florida's winner-take-all scheme for awarding delegates. Robert Galbraith /Reuters /Landov hide caption

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Mitt Romney at his state campaign headquarters Tuesday in Tampa, Fla. Joe Raedle/Getty Images hide caption

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Fresh from a confident debate performance, former Massachusetts Gov. Mitt Romney was jaunty as he campaigned at the Hispanic Leadership Network's lunch in Miami on Friday. Charles Dharapak/AP hide caption

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Florida Sen. Marco Rubio speaks at the Ronald Reagan Presidential Library in Simi Valley, Calif. in August. Rubio's dispute with Univision has provoked a boycott of the network's presidential debate.

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