The widow of the late Republican Senator John McCain has thrown support behind the Joe Biden campaign, drawing cheers from the anti-Trump #Resistance, while critics said the endorsement would only embolden the president’s backers.

“My husband John lived by a code: country first. We are Republicans, yes, but Americans foremost. There’s only one candidate in this race who stands up for our values as a nation, and that is Joe Biden,” Cindy McCain said in a series of tweets on Tuesday night.

Joe and I don’t always agree on the issues, and I know he and John certainly had some passionate arguments, but he is a good and honest man. He will lead us with dignity.

He will be a commander in chief that the finest fighting force in the history of the world can depend on, because he knows what it is like to send a child off to fight.

Ahead of the tweets, Biden himself reportedly announced the endorsement during a fundraiser earlier on Tuesday, saying McCain was lending him support after learning that Trump had denigrated US soldiers as “losers” and “suckers” – apparently referring to an uncorroborated story in The Atlantic in early September, which relied solely on anonymous sources.

The ringing endorsement was soon hailed by a litany of self-avowed #Resisters, including the Lincoln Project, a Republican-led NeverTrump outfit, as well as a member of Biden’s own campaign team.

Cindy McCain is a #LincolnVoter.

You are an American hero. We desperately miss your husband. Thank you.

🇺🇸🇺🇸🇺🇸 Thank you @cindymccain !!

McCain’s support for the former VP may not have come as a surprise for some, as she had already appeared in a video message at the Democratic National Convention, though at the time she refrained from an outright endorsement and spoke instead about the cross-party relationship between Biden and her late husband.

Biden detractors were not impressed with McCain’s move, some insisting that an endorsement from a “swamp creature” would only give voters another reason to back Trump, while others argued Biden and McCain had “much in common” as “corporatists” of their respective parties.

Swamp creature Cindy McCain will endorse Joe Biden, in case you need another reason to vote for Trump.

Not the greatest of breaking news. CNN knows the McCain family and the Bush family hate Trump.Endorsements from these establishment people are not going to change opinion.All CNN does is make trump followers more resolved.

Biden and McCain have much in common. One is a corporatist Democrat the other corporatist Republican. Same thing.

Netizens also noted other “values” Biden and the former senator might have in common, with “higher taxes,”“gun confiscation” and “endless foreign wars” among the suggestions offered. Some critics also attempted to banish McCain from the GOP altogether, insisting she and her husband are “not Republicans,” one even going so far as to call the former lawmaker a “traitor.”

You are not a Republican. Never were.

You’re not Republicans. And he was a traitor.

McCain’s endorsement of Biden is not the first to come from the Republican camp. Before her, the former governor of Ohio, John Kasich, as well as four former GOP cabinet secretaries – Chuck Hegel, Ray LaHood, Colin Powell and Christine Whitman – each backed Biden’s 2020 election bid.

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