Major poll presents ominous sign for Donald Trump about his convention

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A Gallup poll released on Monday provided some ominous signs for Donald Trump.

The poll found that 51% of the 1,000 adults surveyed said that they were less likely to vote for Trump following the Republican National Convention.

Only 36% said that they were more likely to vote for the New York businessman after he was officially named the GOP nominee.

Monday's poll was the first instance, since Gallup began tracking Republican and Democratic conventions in 1984, that voters were less likely to vote for the party nominee in the immediate aftermath of his or her convention.

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Aside from the Democratic conventions in 1984 and 1992, where Gallup did not have data, its dataset encompassed 16 party conventions, including the recently wrapped-up DNC in Philadelphia, where 45% of respondents said that they were more likely to vote for Democratic nominee Hillary Clinton. Gallup found that 41% of respondents were less likely to do so.

The previous low margin in the Gallup survey was following the 2012 GOP convention, where 40% of respondents said that they were more likely to vote for GOP nominee Mitt Romney, while 38% said they were less likely to do so. The all-time high was following the 1992 GOP convention, where 60% of respondents said that they were more likely to vote for President George H.W. Bush. Just 15% said that they were less likely.

Trump received a polling bump after his convention concluded, but it was quickly erased by Clinton's bump following the DNC. The Manhattan billionaire is still locked in a tight race against the former secretary of state, as the RealClearPolitics polling average showed Clinton with a 2.2% lead over Trump.