https://www.newsweek.com/more-republicans-back-biden-unprecedented-rebuke-sitting-president-1511558
Rosario Marin, who served as Treasury Secretary under George W. Bush and recently joined the super PAC supporting Biden, said that six months ago people weren't thinking about switching parties, but the coronavirus outbreak "shined a bright light on his deficiencies as a leader and as an administrator."
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Where many in the military gave Trump the benefit of the doubt in 2016, Miller said, there has been a cascade of former military leaders coming out against Trump, whom Republican groups see as the "most credible messengers" in their quest to see Biden defeat Trump.
"This fall, it's time for new leadership in this country—Republican, Democrat or independent," retired Navy admiral William H. McRaven, who led the Osama bin Laden raid told the Times. "President Trump has shown he doesn't have the qualities necessary to be a good commander in chief."
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More high-profile Republican endorsements of Biden are coming, she said.
"It would be a relief that [Trump's] no longer going to be there," Marin said, envisioning a Biden victory on election night. "A sigh of relief that they no longer need to make excuses, they no longer need to cover for him."