Comedian and sitcom writer Michael Loftus said that high-profile Democrats appear on late-night television shows to make campaign announcements because they know they will be asked "softball" questions.

His opinion comes after Sen. Kirsten Gillibrand (N.Y.) announced Tuesday on "The Late Show" that she has formed an exploratory committee for a 2020 presidential run.

Gillibrand is the latest Democratic politician to discuss their 2020 plans on Stephen Colbert's talk show, joining Sens. Kamala Harris (Calif.) and Bernie Sanders (Vt.) and former Housing and Urban Development Secretary Julian Castro.

"Look at the way [Colbert] fawns all over these guys," Loftus said Wednesday on Fox & Friends. "If you fail on Colbert, get out of the race. ... I don't trust you to negotiate with anybody if you can't do good on that show."

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Castro announced his campaign for president last weekend, while Sanders and Harris have yet to announce their plans for 2020.

Loftus predicted that many other Democrats will announce their bids for the White House on late-night TV.

"The entire late-night arena ... it's all just the advertising arm of the Democratic Party. It's a big, giant safe space for them," he said.

He also criticized former Rep. Beto O'Rourke (Texas) and Sen. Elizabeth Warren (Mass.) for awkwardly using social media as a way to connect with their supporters.

Warren was widely mocked for cracking open a beer during a livestream, and O'Rourke received similar criticism for streaming his trip to the dentist.

"How completely un-presidential could you be? ... I don't trust these people to negotiate a Triple-A discount at a Holiday Inn," Loftus said. "How are they gonna go toe-to-toe with China or Russia?"

Watch more from "Fox & Friends" above.

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