Republican Donald Trump is more popular with Michigan's working-class white voters than past GOP candidates, and has pledged to back out of the treaty some blame for the loss of countless Rust Belt jobs. At stake is the white, working-class vote, which Trump says he can turn out in droves, thereby putting upper Midwestern battlegrounds long carried by Democrats into competition in his quest for the 270 electoral votes needed to win the presidency. Trump says his appeal to disaffected workers has taken hold, and can put in play Wisconsin and Pennsylvania, states carried by Democratic presidential candidates since the 1980s. Trump's trade position, a sharp departure from Republican orthodoxy, has the appearance of moving to Clinton's left on trade, and sounds an alarm for her to address the treaty in Michigan, say Democratic activists in the state. [...] Clinton's advantage among union members in surveys over Trump is the same as Obama's was in over Arizona Sen.