MARSHALLTOWN, Iowa (CBS NEWS) -- At one town hall after another, congressional Republicans on recess this week have been getting an earful, and now another issue is testing their hearing.

Firing the head of the FBI as the bureau investigates Russian ties to the Trump campaign fired up the crowd at Iowa Congressman Rod Blum's Thursday town hall, reports CBS News correspondent Dean Reynolds.

"If Trump was guilty of something, would he fire the FBI director?" Blum asked.

"Yes!" the crowd yelled.

"Because that's a pretty dumb move," Blum said. "I get it. I mean I get it. You hate the president. I get it."

Blum represents a district that twice voted for Barack Obama but turned red in November. In Marshalltown, Blum was repeatedly forced to defend the president.

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