Justin Sullivan/Getty Images
NBC, The Associated Press, The New York Times, and Fox News all called the race for Clinton, who quickly thanked her supported on Twitter.
With 70% of precincts reporting, Clinton captured 52.3% support, while Sanders garnered 47.7% support.
"To everyone who turned out in every corner of Nevada with determination and heart: This is your win. Thank you," she wrote.
Long seen as a key part of her "firewall" against a surge in support for Sanders, the state's notoriously unreliable polls showed a tightening race in recent weeks following Sanders landslide win in the New Hampshire primary.
Clinton took to Twitter to thank her supporters.
To everyone who turned out in every corner of Nevada with determination and heart: This is your win. Thank you. -H
- Hillary Clinton (@HillaryClinton) February 20, 2016
The feeling is mutual, Nevada. pic.twitter.com/Z32JkpNKAp
- Hillary Clinton (@HillaryClinton) February 20, 2016