Story highlights Democratic nominee Clinton leads Republican rival Trump by a healthy margin

Both in a one-on-one matchup and when third-party candidates are included

(CNN) The post-convention polls are in, and they consistently show Hillary Clinton entering the next phase of the presidential election campaign with the upper hand over Donald Trump.

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.

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