U.S. Sen. Cory Booker (D-N.J.) pledges to hold the Senate floor for "as long as I'm physically able" in a filibuster that began on Monday night. Booker is protesting what he called a reckless and unconstitutional attack on America by President Donald Trump. (Photo by congress.gov via Getty Images) Getty Images

Senator Cory Booker's record-breaking speech has stirred presidential speculation, but experts told Newsweek it's too early to know how viable of a candidate he may be in 2028.Newsweek reached out to Booker for comment via his office and political team.

First off, it was not a filibuster. But Booker's historic 25-hour speech broke the Senate record, and was a startling challenge to Trump’s agenda