Donald Trump’s favorable rating is now roughly equal to Hillary Clinton’s favorable rating. To the Trump skeptic, the result might be viewed as a short-lived post-convention bounce for the Republican nominee. To the Trump fan, it might be viewed as a sign of things to come as the summer turns to fall. History suggests that it really could be either: Sometimes how voters view a candidate immediately after the conventions sticks — sometimes it doesn’t. (That’s something to keep in mind as we watch Clinton’s numbers now that her convention has wrapped up.)
The post-convention favorability polls have been a hair more predictive than the pre-convention polls, but I wouldn’t make too much of the difference — a number of candidates who had great conventions ended up finding popularity fleeting afterward. You can see this in the table below, which shows the net favorability of both major party nominees in the final CBS News polls of every campaign since 1980, compared to their net favorability in the CBS polls taken before and after both conventions:
Net favorability numbers are from before and after both conventions each election cycle.
Source: CBS NEWS
Jimmy Carter was very unpopular in 1980 before the conventions, but saw his net favorability rise 24 percentage points by the time they were over, basically matching Ronald Reagan’s rating (Reagan’s fell during the convention period). Reagan, of course, went onto win in the fall easily. We probably should have viewed Carter’s improvement skeptically given his job approval ratings still weren’t very good throughout the period.
John McCain suffered a similar fate in 2008. After a strong convention, and the initially successful rollout of his running mate, Sarah Palin, McCain got an 8 percentage point bump; then-Sen.Barack Obama’s …