Las Vegas (CNN) Polls heading into the Nevada Democratic caucuses showed the two contenders neck-and-neck, so Hillary Clinton can thank the late deciders -- people who made up their minds in the least few days -- for the victory.

More specifically, she can thank 29-year-old Vanessa McCallum. Saturday's decision was difficult for her down to the final moments, when she had to decide whether to sit on the Bernie Sanders or Clinton side of the caucus at Caesar's Palace.

"It's a heart versus logic thing," said McCallum, a Las Vegas massage therapist who ultimately caucused for Clinton. "I love Bernie Sanders. And I love him because he's the only candidate who is enticing everybody -- the youth vote -- to get up, get out and do something. I respect his policies. I respect him as a person."

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