Nikki Haley has pulled ahead of Ron DeSantis in the polls, but Donald Trump remains the frontrunner by double-digits as voters prepare to brave sub-zero temperatures. ABC News' Em Nguyen reports. SUBSCRIBE to ABC NEWS: https://bit.ly/2vZb6yP Watch More on http://abcnews.go.com/ LIKE ABC News on FACEBOOK https://www.facebook.com/abcnews FOLLOW ABC News on TWITTER: https://twitter.com/abc #election #2024 #iowa #abcnews #news