The Republicans were pretty much salivating at the prospect of running against Bernie, that pretty much says it all.
The democrats were salivating at the chance to run against trump.
To answer the op, maybe. I believe that the folks who voted in the last election were the same people that always vote and those people mostly always vote R or always vote D. Bernie would have had those votes and may have energized other liberal voters to come out.
Trump did well in traditionally Democratic rust belt states largely because Hillary basically ignored those states. Bernie's message was pretty much the same as Trump's with less but not absent anti-foreigner rhetoric. He might have gotten those rust belt states that Hillary failed to get. So, Maybe.