FILE - Democratic presidential nominee and former Vice President Joe Biden arrives to speak after touring a plumbers union training center in Erie, Pennsylvania on October 10, 2020. ( ROBERTO SCHMIDT/AFP via Getty Images)With the backdrop of a union facility in a key battleground county of Pennsylvania, Joe Biden on Saturday blistered President Donald Trump as only pretending to care about the working-class voters who helped flip the Rust Belt to the Republican column four years ago.“Anyone who actually does an honest day’s work sees him and his promises for what they are,” Biden told a masked, socially distanced crowd at a training facility for plumbers and other tradespeople.The Democratic challenger has hammered Trump on the economy in.