Thompson Square emerged as an early winner at the Academy of Country Music Awards in Las Vegas. ACM CEO Bob Romeo surprised the husband-and-wife duo of Keifer and Shawna Thompson with the news during Saturday night's (March 31) ACM Salute to the Military concert. In winning the vocal duo of the year, they edged out Sugarland (the reigning duo of the year), Steel Magnolia, Montgomery Gentry and Love and Theft. Winners in the other categories will be revealed during the ACM Awards show airing Sunday (April 1) at 8 p.m. ET/PT on CBS. Reba McEntire and Blake Shelton will host the event at the MGM Grand Garden Arena.