I can't see a scenario where democrats lose FL while simultaneously winning MT and WV. It just doesn't seem logical. If democrats lose this, they probably are having a very bad night, at least in the senate.
Why? MT and WV are still very Democratic-friendly down ballot, Tester and Manchin are far stronger incumbents than Nelson, and the GOP candidates in MT/WV are not only getting heavily outspent but also running incredibly poor campaigns.
Heck, WV elected a Democratic governor by 7 while voting for Trump by 42 points, and Morrisey is almost certainly less popular than Bill Cole was.