Supporters of President Trump began a "lock her up" chant when the president spoke about a viral moment during the Kavanaugh hearings involving California Sen. Dianne Feinstein.

Texas Republican Sen. John Cornyn asked Feinstein during the hearings whether she leaked the identity of accuser Dr. Christine Blasey Ford to the press.

Feinstein appeared surprised at the question, and turned to her staff before declaring that she hadn't and had no knowledge of who had done so.

Trump was in Council Bluffs, Iowa, on the Nebraska border, to stump for several candidates from the two states.

He brought up several potential Democratic 2020 nominees, alleging that Sen. Cory Booker (D-N.J.) "ran Newark into the ground" while mayor there, and ripped Sen. Richard Blumenthal (D-Conn.) as "Da Nang Dick" for inflating his Vietnam War record.

"How about Senator Feinstein, there's another beauty," he said.

The crowd loudly booed the 85-year-old's name, and began chanting "Lock Her Up" -- a chant, that, until that point, Trump supporters reserved for Hillary Clinton.

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Trump smirked at hearing the chant:

"I think they're talking about Feinstein," he remarked.

"Did she leak it? ... 99% [sure]," he said.

He then urged those in attendance to support Republicans in the midterm elections.

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