Which candidate poses the biggest threat to Donald Trump?

Columnist Mark Steyn goes on Hannity to discuss Ben Carsons surge in the polls Watch Sean Hannity talk about Elections, Presidential Primaries, and .\r
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Which candidate poses the biggest threat to Donald Trump? -- Columnist Mark Steyn goes on Hannity to discuss Ben Carsons surge in the polls.\r
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Donald Trump spoke in Vegas today, a man who said hes from Mexico confronted him during his Q&A and said hes “incredibly insulted” by what Trump has .