President Donald Trump questioned the validity of a Fox News poll that showed him losing to several Democratic candidates by significant margins.

Fox News released a poll on Sunday which showed Trump trailing five different Democratic 2020 candidates, by margins of up to 10 points. The survey showed the president losing to former vice-president Joe Biden by 10 points, Sen. Bernie Sanders (I-Vermont) by 9 points, Sen. Elizabeth Warren (D-Massachusetts) by 2 points, and Sen. Kamala Harris (D-California) and Mayor Pete Buttigieg by 1 point. Trump denied the accuracy of these polls, instead choosing to tout a mystery poll that showed the president winning in all 17 swing states. “Something weird going on at Fox,” he tweeted.

As an increasing number of polls predict Trump losing to candidates such as Biden and Sanders, the president has increasingly gone on the defensive by attacking any data that he doesn’t like. Similar to his strategy for dealing with unflattering media coverage, the president is attempting to delegitimize any poll that doesn’t favor him by labeling it as “Fake.”

When the president’s own internal polls were leaked, showing Biden leading Trump by several points, the New York tycoon denied the accuracy of the polls, instead choosing to attack the news outlets that had published the results. Trump also instructed his aides to lie about the polls as well, telling them to assert that the numbers from his own campaign pollsters, several of whom he then fired, were incorrect.

The results of several other recent polls support the data from Fox’s survey, showing Trump trailing several Democratic candidates. A Quinnipiac University poll released last week found that Biden was leading Trump by 13 points and that several other Democratic candidates were ahead of the president as well. It remains to be seen how those numbers will change now that Trump has formally begun his campaign for reelection. With his massive kickoff rally set for Tuesday, and with the Democratic primary debates in almost a week, it’s almost certain that the 2020 field will continue to change in the coming months.