The Gallup poll, which has been tracking U.S. presidents since 1936, records that Trump’s June approval rating of 39 percent is the lowest of elected presidents since Jimmy Carter (1980) and George H.W. Bush (1992) and the unelected Gerald Ford (1976).
As political scientists and Gallup and the political website, 538, point out, approval ratings tend to track November presidential votes and significant change is not common between June and November. Trump’s approval average reported at RealClearPolitics, which is slightly better at 42 percent, has rarely left the mid to lower 40s.
Recent presidents’ approval ratings in the table below shows their January 1, June and Election Day approval ratings. Notice the clear correspondence of the June approval with the final approval and Election Day result. At 39 percent by Gallup, or even Trump’s 42 percent average, he’s in serious trouble without changing the direction of his campaign.