Lindsay Lohan is giving teen rival Hilary Duff a run for her Billboard spot. The 18-year-old Mean Girls star has signed a record deal with Tommy Mottola's Casablanca Records. Mottola, who helped shape the careers of such megastars as Celine Dion, Jennifer Lopez and ex-wife Mariah Carey, will most likely create a top-40 vibe for the actress. The pop-princess-in-training's singing voice has been heard in her films Freaky Friday and Confessions of a Teenage Drama Queen. Lohan's first album is expected to be released by the end of the year.