WASHINGTON – Sen. Susan Collins, who is facing a tough reelection battle in the fall, gave a "mixed" review of President Donald Trump's public statements on the coronavirus outbreak.

The Maine Republican told Politico on Tuesday that when the president is effective, he defers to health experts at his almost daily news briefings on the COVID-19 pandemic. But she said his occasional tangents or dust-ups with reporters were counterproductive.

"It’s been very uneven. There are times when I think his message has been spot on and he has really deferred to the public health officials who have been with him at these press conferences," Collins said in the interview. "And then there are times when I think he’s been off message and has brought up extraneous issues. So I think it’s been mixed."

She said his conflicts with reporters were not "helpful" and "when he gets off message or brings up issues that have nothing to do with the coronavirus, it is not reassuring to the American people."

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Last month, Collins told the Bangor Daily News that Trump should "step back" from the briefings and said the administration's statements on the virus had been "inconsistent."

A moderate, Collins has criticized Trump on a number of occasions. She did not vote for Trump in 2016 and has declined to say if she plans to in November.

But Collins has been chided by critics for often expressing concern about Trump's words or deeds and then consistently voting with him on controversial issues such as the 2017 tax cut, Brett Kavanaugh's confirmation to the Supreme Court and Trump's impeachment trial.

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She is considered one of the most vulnerable Republican senators up for reelection this year and political contributions from across the nation indicate that win or lose, her quest for a fifth term will be a very costly campaign.

On Wednesday, Majority Forward, a liberal political action committee, launched a new ad condemning Collins for telling the Bangor Daily News in an April 2 interview that she thought Trump "did a lot that was right in the beginning" of the outbreak.

"For example, he acted very early to ban travel to China, and that was a move, an action that he took that undoubtedly saved lives," she said. "I think in the beginning there were times when he was speaking about what he hoped would happen rather than relying on the data and information of his experts. That has changed, and I’m glad that it has."

During that interview, she said Trump's initial statements on the virus "may have given some people a false sense of security," but that the briefings with health experts Anthony Fauci and Deborah Birx were "far more helpful to the American people."

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Sara Gideon, speaker of the Maine House of Representatives, is the Democratic primary frontrunner to take on Collins. Two recent polls indicate a tight race with Gideon holding a narrow lead.

A Critical Insights poll conducted in March found Collins' job approval rating to be at 37% – four percentage-points lower than a year before, which was the first time the survey found her approval rating below 50%. Her disapproval rating was the highest the survey has found at 52%. By contrast, 59% of Maine voters approved of the job independent Sen. Angus King has done while 21% disapprove.