Now Playing: ABC News’ Jonathan Karl breaks down key midterm races
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Now Playing: Sen. Joe Manchin expected to win re-election
Now Playing: Ron DeSantis to become Florida governor after Andrew Gillum concedes
Now Playing: Democrats take control of the House
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Now Playing: Republican Kevin Cramer expected to defeat incumbent Heidi Heitkamp in North Dakota
Now Playing: Republicans will retain control of the Senate, ABC News projects
Now Playing: Ted Cruz expected to defeat Beto O’Rourke in Texas
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Now Playing: Colorado’s Jared Polis on track to become 1st openly gay governor
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