The Nashville-based trio's huge crossover hit spent five weeks at the top of the Billboard country chart.
"Thank God, thank our families, thank the fans so much," singer Hillary Scott said in accepting the award at the MGM Grand in Las Vegas during a show broadcast live on CBS and hosted for a 12th time by Reba McEntire.
She was flanked by bandmates Charles Kelley and Dave Haywood who make up the trio, which leads all artists with seven nominations.
The show kicked off with Carrie Underwood and Miranda Lambert performing a raucous version of Creedence Clearwater Revival's 1970 rocker "Travelin' Band."
Underwood, 27, and Lambert, 26, who both first gained fame on TV — American Idol for Underwood and Nashville Star for Lambert -- were joined for a verse by former Creedence leader John Fogerty.
Underwood is nominated for the night's top prize, Entertainer of the Year, an award she won last year for the first time, and earlier in the weekend Lambert won Video of the Year for "White Liar."
Underwood is competing for the fan-voted Entertainer of the Year against a field that includes a larger number of eight nominees, including veteran Kenny Chesney, who won it four years in a row until she snapped his streak in 2009.
In winning in 2009, Underwood became only the seventh woman to take the award, and her big night felt like a changing of the guards for country music.
Taylor Swift, perhaps the hottest new country music star of the past few years, is considered by some to be the favorite to win Entertainer of the Year. A win by the 20-year-old, who has been nominated for five awards, would cement the trend in young female country singers rising to stardom.
Chesney, who sang his hit single "Ain't Back Yet" during the broadcast, has said that he will largely take a break from recording and touring in 2010.
Also earlier in the weekend, Blake Shelton and Trace Adkins took home the award for Vocal Event of the Year for "Hillbilly Bone," which the duo performed during the show.
