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In his monologue today, Greg Gutfeld explained how Donald Trump's comments about former Miss Universe Alicia Machado's weight problems help Hillary Clinton.

Gutfeld said that this story would have been forgotten shortly after Clinton mentioned it during Monday's presidential debate, but Trump just wouldn't let it go.

"It's proves how vital preparation really is," Gutfeld said. "Hillary's camp did their homework and knew what would stick in his mind. They found this beauty queen, lobbed it his way, and he swung right at it."

"Essentially, Hillary dug a hole and said, 'Hey, Donald, here's a great hole to fall in!'"

Gutfeld lamented that there are countless more important things that the candidates and the mainstream media could be talking about, including the economy, ISIS and immigration.

"The more they talk about Donald, the less they talk about her. To her credit, she turned Trump into her own best defender."

Kimberly Guilfoyle agreed with Gutfeld, suggesting that Trump "let it go" when he's attacked like this.

She said that if he responds with something like, "Lets get back to the relevant questions," he can better control the narrative on the campaign trail.

Juan Williams said Trump is simply unable to avoid feuds, whether it's the Khan family, Rosie O'Donnell or U.S. District Court Judge Gonzalo Curiel.

"He just loves to fight," Williams said. "He's a schoolyard bully. It's what he likes to do."

Watch more above, and share your thoughts in the comments.

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