Those unfavorable numbers explain it all. Trump is more favorable in Ohio than Hillary is. That makes the difference.
Trump also has better favorables that Hillary in PA. They have the same exact numbers in FL. Of course Bernie's is much better than both of theirs.
Notice that Trump has solid leads when asked about the economy, and also leads on terrorism in all 3 states. Hillary is such a terrible candidate.
Bernie is just like Kasich, hes well liked because theres no way hes the nominee. If the PPP poll from last night is any indication though, even thats changing(the well liked part).