An analysis from the ad-scoring outfit Ace Metrix ranked multiple political ads from Bernie Sanders’ campaign among the most effective of the 2016 presidential race so far.

Out of the 152 television and digital ads run by presidential candidates or independent super PACs since the middle of July last year, Sanders’ Dec. 28 spot, "Social Security," scored the highest aggregated total across more than half-a-dozen metrics like watchability, relevance and credibility as determined by a politically and demographically balanced panel of 500 people. Republican candidates snagged only two of the top 10 slots, a showing that could bode ill for that party’s eventual showing in November.

Of course, ad engagement isn’t the same as platform persuasiveness, but the data thus far closely tracks the results from both national polls and surveys in early voting states. For example, in addition to scoring ads according to the preferences of a representative sample of the population, Ace Metrix also broke down support by party.
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Here are the top-ranked 2016 presidential campaign ads as determined by Ace Metrix:

Mixed Field

"Social Security," Bernie 2016. Ace Score: 550
"Real Change (Revised)," Bernie 2016. Ace Score: 532
"Works For Us All," Bernie 2016. Ace Score: 523
"Mari," Bernie 2016. Ace Score: 519
"We The People," Carson America. Ace Score: 517
"Real Change," Bernie 2016. Ace Score: 514
"Working Families," Bernie 2016. Ace Score: 512

Among Independents

"Social Security," Bernie 2016. Ace Score: 535
"Why," Carson America. Ace Score: 531
"Real Change (Revised)," Bernie 2016. Ace Score: 528
"Works For Us All," Bernie 2016. Ace Score: 523
"We’re All Americans," Believe Again (Jindal)". Ace Score: 517
"Mari," Bernie 2016. Ace Score: 508