It's likely that most who entered the TLA on Wednesday knew about Meghan Trainor's back-story. That's why her show was sold out, with kids, tweens, and parents drawn to the now-21-year-old's message, as well as her brand of merry synth-pop, doo-wop, and such.

Trainor was a Nantucket-raised, plus-size teen dissed by girl frenemies and jock boys for not having a tall, stick-figure frame. Luckily, the young Trainor had confidence in her big talent: a brassy singing voice, a way with funny lyrics, a winning personality, and musical-theater panache. She also just happened to be "all about the bass." Hence her 2014 bubblegum hit of the same name.

Success is the best revenge, and Trainor - cheery in a short, swishy skirt - exuded delicious confidence on stage. Although she didn't have the bawdy image, catty comic timing, or wide vocal range of a Bette Midler, she showed she is heading in Midler's direction. Entertaining as all get out, with more talky asides than a Eugene O'Neill play, Trainor, when singing, fit her deepest feelings into kiddish, humorous lyrics such as those on "Credit" and its take on losing the wrong man ("Had him brushing his teeth, even flossing,/ Got him looking like Ryan Gosling"). The zealous doo-wop of "Dear Future Husband" was silly with a genuine sense of hope and yearning. "Walkashame" was a bouncy throwaway, but still cute.

Not every lyric was fun and games, and not every tune was cutesy (she's written hearty songs for Rascal Flatts). The ballad "Like I'm Gonna Lose You" was tinged with fatalism fatality ("Gonna hold you like I'm saying goodbye"). Although the ukulele in "Title" seemed to promise sweet introspection, the song turned out to have a bittersweet bitchiness to it. The lusty Motown-ish "Lips are Movin" sounded more grungy and Amy Winehouse-ish than any of Trainor's current young chart contemporaries. Oddly enough, when she got to her giddy hit, "All about the Bass," she - at least the arrangement - could have used more bass in the mix. Maybe next time. If Wednesday was any indication, Trainor is going to be around for a while.