
REUTERS/Scott Audette (L), Javier Galeano (R)
Donald Trump and Hillary Clinton look likely to battle it out for the White House.
The analysis showed that stories told by real citizens had the most impact among the most crucial voting group: independents.
According to Gallup polling, independent voters currently make up 37% of the US electorate.
Of the 24 anti-Trump ads that Ace Metrix analyzed, three of the five most effective among independents focused on the so-called "scam" of the now-defunct Trump University.
The video advertising analysts gave each advert an "Ace Score," based on metrics like "Attention," "Watchability," "Persuasion," "Agreement," and "Information Seeking." The score is intended to show the effectiveness of the ad, and the likelihood of it changing the way a viewer will vote.

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Trump University was the target of many of the most effective anti-Trump ads.
Another of the most effective ads was "Big Money," by Our Principles PAC - a Republican super PAC [political action committee] set up specifically to derail the Trump campaign. The ad made claims that Trump had employed and profited from illegal immigrants.
By contrast, Republican voters were most convinced by anti-Trump ads which focused on the billionaire candidate's stance on key Conservative issues, Ace Metrix found.
Early sparring between pro-Clinton campaigners and Trump through ads has already infuriated the Kremlin. And things look set to get even dirtier, as the two begin to divert their campaign resources against each other - assuming they both win their party nominations.
Below are the top five most effective anti-Trump ads among independents, according to Ace Metrix.