POLL: Hillary Clinton soars to 15-point lead over Donald Trump
The poll, conducted by McClatchy/Marist, showed the Democratic nominee with a massive 15-point lead over her Republican opponent.
Clinton's edge was at 48% to 33%, a drastic difference between the 42% to 39% advantage that the poll found her to have in July.
No poll posted to RealClearPolitics since Trump locked up the Republican nomination in May showed Clinton with a larger lead.
It's the latest in a string of terrible polling news for Trump, who saw his support collapse nationally in this week's Fox News poll and in three major battleground states.
"This is coming off the Democratic convention, where a bounce is expected," Lee Miringoff, director of the Marist Institute for Public Opinion in New York, told McClatchy. "What you don't want is to have the worst week of your campaign."
Trump's poll numbers have taken a beating amid a feud with a military family that was critical of him at the Democratic convention.
He has also lately said that the fall election will be "rigged" against him, expressed more positive feelings toward Russia, and said that he is not ready to endorse House Speaker Paul Ryan or Sen. John McCain of Arizona - two of the most prominent Republicans in Washington - in their primary races later this month.