The CNN Poll of Polls incorporating the results of six major polls -- all conducted after the party conventions concluded in late July -- finds Clinton with an average of 49% support to Trump's 39%. When third party candidates Gary Johnson and Jill Stein are included, the margin remains the same, with both candidates losing the same amount of support to land at 45% for Clinton to 35% for Trump, with Johnson at 9% and Stein at 5%.
The new averages reflect a sharp increase in support for Clinton compared with pre-convention polls. The last CNN Poll of Polls, analyzing the results of five national, live-interviewer telephone polls conducted before the GOP convention began, found Clinton ahead 45% to 41%.
There was not enough polling in the short window between the end of the Republican convention and the beginning of the Democratic gathering for a Poll of Polls analysis to be conducted, but both live-interviewer telephone polls conducted in that time found Trump ahead by a small margin heading in to the Democratic convention.
But across nearly all polls released following the Democrats' nominating convention in Philadelphia, Clinton has regained a significant advantage.
The candidate holding a lead after both major party conventions are complete nearly always goes on to win the presidency in recent history. One exception was Al Gore in 2000, who held a 4-point lead in CNN/USA Today/Gallup poll conducted after the completion of his convention. Gore, the sitting vice president at the time, went on to win the popular vote by about half a percentage point while losing to George W. Bush in the Electoral College.
This year, however, there is more time than usual for voters to change their minds between the conventions and the elections. With parties hosting conventions in July this year, they are the earliest since 1960.
Comparing the two-way and four-way ballot tests, the Poll of Polls suggests Johnson is faring better than most third party candidates do once the chaos of the primary and caucus nomination process is over. Typically, support for third-party candidates dips once the major-party tickets are set, but Johnson's support appears to be holding. At 9% in the Poll of Polls average, he lags behind the 15% threshold he'll need to meet to get on stage at the presidential debates this fall.
This CNN Poll of Polls covers polls conducted between July 29 and August 4. All were conducted by telephone using live interviewers, with results representing the opinions of registered voters nationwide. Polls included are the CNN/ORC Poll, the CBS News Poll, the Fox News Poll, the NBC News/Wall Street Journal Poll, the Marist/McClatchy Poll and the ABC News/Washington Post Poll. The Poll of Polls does not have a margin of sampling error.