Hillary Clinton and Bernie Sanders both feature. AP TV adverts are a key part of any presidential campaign. They offer a rare opportunity for the candidates to present their message directly to voters, inside people's living rooms, but outside of the media's filter.

And new data shows that Democrat hopeful Bernie Sanders has dominated this area of the 2016 race so far, according to Ace Metrix, which measures the impact of video advertising. Not only did Sanders' "Social Security" ad earn the highest marks in the study, but his videos took up eight spots in the top 12 list.

The video advertising analysts gave each advert an "Ace Score," based on data collected from 500 respondents per ad, using a balanced sample of voters. The score was combined from 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.

Check out the 12 most effective ads of the 2016 campaign so far.