While certainly not holding the same kind of freakish obsession as that dude who's starring in the “Twilight” movie, Jason Mraz still has an uncanny ability to get the ladies screaming. Maybe it's the way he way he stands onstage with that “Aw shucks” demeanor. Maybe it's his tongue-in-cheek lyrical sarcasm and tempered guitar play. Maybe it's the unrequited sweetness of his latest hit single, “I'm Yours.” Either way, the Mechanicsville native can still sell out a show (or two, or three, or all of them). Try if you can to catch Mraz's charm at two shows at the National on Wednesday, Nov. 26, and Friday, Nov. 28, at 6:30 p.m. $35. 612-1900. — Alexander Chang