On “American Idol,” Carrie Underwood was the country girl who never sounded comfortable trying to come on tough. Especially when she was belting Heart’s “Alone,” the top Idol pick for wussy girls copping an attitude. For her debut, Some Hearts, Underwood dabbled in mainstream pop, but the smash “Before He Cheats” proved her heart was all the way country; the way she sang about a rival singing “some white-trash version of Shania karaoke” was perfect. Carnival Ride is more country and therefore more confident. She goes for the girl-next-door cred long since given up by Faith Hill in uptempo gems like “The More Boys I Meet” (“The more I love my dog”). She rocks out in “Flat on the Floor,” wailing, “You can’t knock me off my feet/When I’m already on my knees.” But the most fun is “Last Name,” where she gets wasted and runs off to Vegas with a guy she doesn’t know. “My mama would be so ashamed” – now that sounds like the real Carrie.