Many of the same pollsters who were wrong about President Donald Trump's chances in the 2016 election now have him polling as the least popular commander-in-chief in modern U.S. history.

But could their data be skewed against Trump once again? Well, he certainly thinks so...

On "Fox & Friends" today, Mark Penn, a pollster and former chief strategist for the Clintons, agreed that the polls are again underestimating Trump, with approval ratings often in the low 40s or even lower.

Penn explained that the polls are finding approximately 95 percent of Trump's supporters are still backing him, which means his approval rating should be close to the 46 percent of the popular vote he received in the election.

He added that about 10 percent of the people who didn't vote for Trump approve of him, which should bump him up several more percentage points.

Penn said another problem with polls is that they generally haven't covered Trump's message points - like tax relief, jobs, sanctuary cities or the border wall - just the opposition's.

When taking all that into consideration, he said he would set the president's approval rating at 48 percent.

"I think that's a realistic assessment of where the electorate is," Penn said. "It's not as bad as people think. Nobody, him or the Democrats, has crossed 50 percent yet. That's what they should be fighting for."

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