IT BEGINS: One of the most vulnerable Senate Republicans just backed off supporting Donald Trump

A Republican senator from Illinois announced Tuesday that he would not support Donald Trump, his party’s presumptive nominee for president, in November.

Mark Kirk’s statement was issued amid a firestorm in the Republican Party about Trump’s attacks on a federal judge, which many have characterised as racist. And it came after the senator said he would support Trump if the real-estate mogul won the nomination.

“I have spent my life building bridges and tearing down barriers — not building walls,” Kirk said in the statement. “That’s why I find Donald Trump’s belief that an American-born judge of Mexican descent is incapable of fairly presiding over his case is not only dead wrong, it is un-American.”

The statement continued: “As the Presidential campaign progressed, I was hoping the rhetoric would tone down and reflect a campaign that was inclusive, thoughtful and principled. While I oppose the Democratic nominee, Donald Trump’s latest statements, in context with past attacks on Hispanics, women and the disabled like me, make it certain that I cannot and will not support my party’s nominee for President regardless of the political impact on my candidacy or the Republican Party.”

Kirk is up for re-election in the Senate. Politico called him “the most endangered Republican senator in the country,” noting that Kirk “isn’t just distancing himself from the rest of the GOP — he’s fleeing from it.”

While Kirk might be the first Senate Republican to un-endorse Trump for president, others in the party have condemned his comments on US District Judge Gonzalo Curiel, who is presiding over lawsuits related to the now-defunct Trump University.

Trump has repeatedly said Curiel, who was born in Indiana to Mexican parents, cannot be impartial because “he’s a Mexican.” Trump argued Curiel’s heritage is relevant because of Trump’s promise to build a wall along the US-Mexico border if he’s elected in November.

House Speaker Paul Ryan called Trump’s remarks “the textbook definition of a racist comment.”

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