The 23-year-old singer is stepping out into a solo career after performing with a band called Hey Monday. Her victory over Scottish native Terry McDermott and long-bearded Nicholas David was announced at the end of a two-hour show Tuesday.
"The Voice" has grown into a hit for NBC and was the key factor in the network's surprising success this fall.
The show's status was affirmed by the stream of hitmakers who performed on the finale. They included Rihanna, Bruno Mars, the Killers, Smokey Robinson and Peter Frampton.