A third of Biden supporters believe the idea that Saturday’s assassination attempt on former President Trump was staged and not intended to kill him is credible, according to a Morning Consult poll. 33 percent of polled Biden supporters indicated they were open to believing the troubling conspiracy theory, a higher number than the overall contingent polled. Only 20 percent of total people polled said they found the conspiracy credible. The majority of voters, 62 percent, found the notion to be unsubstantiated, according to Morning Consult. The concerning conspiracy theory has earned credibilit…