A recent poll of a single Midwestern TV market seemed to prove that the cable sports network ESPN has lost viewers because of its liberal political slant. Now, a follow-up survey has revealed the same results in up to 43 other major TV markets.

For several years, conservatives, including Breitbart Sports, have said that ESPN’s left-wing bias has driven away millions of viewers. Many TV analysts have said there is no real proof of the claim despite the anecdotal evidence of fans on social media complaining that ESPN won’t “stick to sports.”

Early in May a poll emerged showing that Republicans had begun turning away from ESPN, but it was still just an opinion poll, not hard data.

That began to change with the work of TV data service Deep Root which found that viewers who identify as Republican really had quit watching the cable sports network, at least in one major TV market.

Deep Root focused on a single swing election state to gather its viewership data over a two-year period. The company chose the Cincinnati, Ohio, market and found that a large number of center-right viewers had given up ESPN because of its liberal bias. Deep Root assumed that Cincinnati viewers were representative of a greater trend.

But, critics said that basing opinions on a single market was meaningless. So, Deep Root went back to the data and looked at 43 major American TV markets, and instead of finding that Cincinnati viewers were outliers, the new data showed the same results all across the country.

The fact appears to be that Republican and conservative viewers have quit ESPN in droves.

Deep Root admitted that its first survey was less than convincing, saying, “Of course, the (appropriate) criticism of our analysis was that it was built on a single market’s worth of data. ESPN’s audiences becoming less Republican and more Democratic in Cincinnati is interesting, but can it be connected to a larger trend?”

So, to find out if the Cincy viewers were representative of the nation as a whole, Deep Root used its same methods on 43 other markets across the nation, including New York City, Philadelphia, and Washington, DC.

The result? “All told, the ESPN audience across the network’s channels was already liberal in 2015 – but it became more liberal in 2016 as Republicans stopped watching,” Deep Root noted.

“In all, 34 of the markets included in our analysis showed the audience of the flagship ESPN network become less Republican in 2016 compared to 2015,” the company claimed. “The ESPN audience became more Republican in only 9 of the analyzed markets.”

Ultimately, Deep Root arrived at the only logical conclusion:

At a time where ESPN and the larger cable industry faces changes to its business model as consumption patterns and methods evolve, our data indicates that ESPN is also facing a partisan challenge. Given ESPN’s own admission that it has become more political – and on-the-record comments from ESPN talent saying that the network’s liberal nature is likely driving away viewers – this problem appears to be largely self-inflicted at a time when the network cannot afford to lose any more of its audience.

Here are some of the company’s other findings:

The ESPN audience became 5% less Republican in 2016 than 2015 across all 43 markets analyzed.

ESPN2’s audience became 10% less Republican during the same time period.

The biggest partisan shift happened on ESPN News, whose audience became 36% less Republican and more Democratic.

ESPNU’s audience became 12% more Democratic in 2016 compared to 2015.

ESPN Deportes – whose audience already skewed very liberal – became 27% more Democratic.

Follow Warner Todd Huston on Twitter @warnerthuston or email the author at igcolonel@hotmail.com.