Donald Trump and Jeb Bush engaged in a back-and-forth exchange during tonight's GOP debate while discussing lobbyists and campaign finance.

Bush, the former governor of Florida, said Trump had tried to lobby him to open the state to casino gambling.

Trump said that claim is "totally false" and promised that if he wanted gambling in Florida, he would have gotten it.

Bush pointed out that in the past Trump has given money to Hillary Clinton and even invited her to his wedding.

Trump said his job as a businessman was to get along with people, but Bush wouldn't let him finish.

Trump, who has often called Bush a "low-energy" candidate, ended the testy exchange by saying, "More energy tonight, I like that!"

Watch the back-and-forth above, via CNN.

Tune in to Fox News Channel after the debate to see Bill O'Reilly, Megyn Kelly and Sean Hannity bring you three hours of live coverage, starting at 11p ET.

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