Another Republican senator is speaking out in defense of the intelligence community whistleblower at the center of President Donald Trump's rage this week.

"Whistleblowers should be protected," Sen. Joni Ernst of Iowa told a constituent at a town hall in Templeton, Iowa, on Thursday. "I stand with Chuck Grassley on this. We have laws in place."

Trump has repeatedly criticized the whistleblower whose complaint led to Democrats launching an impeachment inquiry. The whistleblower revealed the existence of a phone call between Trump and the Ukrainian president where Trump pushed him to investigate former Vice President Joe Biden, his political rival.

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Ernst, who's facing re-election next year, said last week she wasn't concerned about the substance of the call. "I've looked at the transcript; I don't see anything there," she told The Washington Post.

She was pressed on the topic at the town hall on Thursday by a voter named Amy Haskins, who said, "Where is the line?"

"You didn't pledge an oath to the president, you pledged it to our country, you pledged it to our Constitution. When are you guys going to start standing up and actually be there for us?" she said.

Ernst — who has said Trump interviewed her to be his running mate in 2016 — responded that "the president is going to say what the president is going to do. It's up to us as members of the Congress to continue working with our allies making sure that we remain strong in a face of adversity."

Pushed about Trump asking a foreign country to investigate a political rival, Ernst said she's spoken out against corruption in Ukraine in the past and "corruption, no matter where it is should be ferreted out." As for allegations Trump shook down Ukraine by withholding aid, Ernst noted that the Senate Intelligence Committee is looking into the Ukraine allegations and she was "not jumping to any conclusion. We don't have the full story yet. But once we do we can make that determination."

"What about whistleblowers?" Haskins pressed.

"Whistleblowers should be protected," Ernst replied before saying she was in agreement with her fellow Iowa senator, Chuck Grassley, the head of the powerful Senate Finance Committee.

Grassley on Tuesday issued a statement defending the whistleblower, saying: "This person appears to have followed the whistleblower protection laws and ought to be heard out and protected. We should always work to respect whistleblowers’ requests for confidentiality."

The statement did not mention Trump, but came after the president and top allies including Ohio Rep. Jim Jordan and South Carolina Sen. Lindsey Graham said the person's identity should be revealed.

Trump was asked about Republican concerns on Wednesday and said, "I don't care."

"Look, I think a whistleblower should be protected if the whistleblower's legitimate," Trump said — but he said he didn't think this one was.

"He either got it totally wrong, made it up, or the person giving the information to the whistleblower was dishonest."