"American Idol" sources tell TMZ ... the Jennifer Lopez deal isn't dead yet, but if it does flatline ... "Idol's" next choice is country star Shania Twain.
Shania was a hit on "Idol" this past season when she served as guest judge and mentor.
We're told Shania is Plan B.
TMZ has a thought ... What about Britney Spears? She's fun, she kinda knows music and you never know when she'll go off the hinges. And she's endlessly entertaining. Just sayin' ...