(NewsNation) — Robert F. Kennedy Jr., President Trump’s controversial nominee for Health and Human Services secretary, will not get U.S. Senate approval, Bill O’Reilly predicted Monday.

“RFK – he’ll go down,” the commentator said on NewsNation’s “On Balance.”

O’Reilly, who did not elaborate, was speaking about the limits of Trump’s control over Republicans in Congress.

The strong-arming president can more easily keep House GOP members in lockstep behind him, O’Reilly said, but is likely to encounter resistance in the Senate. Republicans have a 53-47 edge in that chamber.

“The Senate is six years,” O’Reilly said, referring to the length of senators’ terms. “Most of those people will still be in office when Donald Trump leaves. So, he doesn’t have the cudgel there that he has on a two-year term in the House.”

Trump already had a close shave in the Senate last week with his Defense Secretary nominee, Pete Hegseth. Three Republican senators — Mitch McConnell of Kentucky, Lisa Murkowski of Alaska and Susan Collins of Maine — voted against the Fox News commentator, but he was confirmed with the tiebreaking vote of Vice President JD Vance.

“Hegseth was lucky. That was really close,” O’Reilly said.

The Senate Finance Committee was expected to consider Kennedy’s nomination Wednesday.