GOP Sen. Mark Kirk Says He Has A Duty To Consider Obama's Supreme Court Pick

WASHINGTON -- Sen. Mark Kirk (R-Ill.), one of the most at-risk GOP incumbents this cycle, has broken with his party and said he's open to considering a Supreme Court nominee put forth by President Barack Obama . 

"I recognize the right of the president, be it Republican or Democrat, to place before the Senate a nominee for the Supreme Court and I fully expect and look forward to President Barack Obama advancing a nominee for the Senate to consider," Kirk writes in a Chicago Sun-Times oped posted Monday afternoon. 

"I also recognize my duty as a senator to either vote in support or opposition to that nominee following a fair and thorough hearing along with a complete and transparent release of all requested information," he added. "The Senate’s role in providing advice and consent is as important and significant as the president’s role in proposing a nominee."

Kirk's comments represent a stark departure from those made by Republican Party leadership . Senate Majority Leader Mitch McConnell (R-Ky.) has warned Obama not to even nominate a replacement for the late Antonin Scalia, because the GOP-controlled Senate will not act on it. McConnell, and the vast majority of his party, argue that the next president should get to choose the nominee -- in hopes, of course, that the next president will be a Republican.

But cracks have started to emerge. Sen. Ron Johnson (R-Wis.), another vulnerable incumbent, initially came out in support of McConnell's position. But since then, he has said he'd be willing to vote on an Obama nominee -- although doing so is still not his preference. 

Sens. Dan Coats (R-Ind.), Susan Collins (R-Maine) and Lisa Murkowski (R-Alaska) have also indicated an openness to looking at a candidate this year. 

Even if Republicans allow Obama's nominee to get a full floor vote, that nominee will face an uphill battle to confirmation: he or she will need the vote of at least 14 Republicans, as well as every single Democrat and the Independents who caucus with them.

Kirk warned Obama against choosing a "partisan or extreme nominee ," instead hoping for someone who can "bridge differences."

"As a 23-year veteran of the U.S. Navy Reserve and as a United States senator, I swore an oath to protect and uphold the constitution," he added. "That oath is to our constitution, not to a party or any one individual, but to the ideals that bind our nation."

Kirk is facing a tough re-election race in a state that leans Democratic and several Democrats are vying to replace him, including Rep. Tammy Duckworth (D-Ill.), the frontrunner. Kirk is also facing pressure from conservatives to obstruct a potential nominee from Obama. 

Influential conservative talk radio host Hugh Hewitt has threatened Kirk and other vulnerable GOP Republicans , urging them not to waiver in the Supreme Court fight. 

"I know for certain that if Sen. Mark Kirk, R-Illinois, votes in any way to advance President Barack Obama's nominee to replace Scalia I will actively support his Democratic opponent ," Hewitt wrote in a recent CNN op-ed. "I'd rather lose the Senate majority with a fight over first principles than the Supreme Court of the United States without a fight."

UPDATE: 4:35 p.m. -- Sen. Jeff Flake (R-Ariz.), the final GOP member of the Judiciary Committee to weigh in, said Monday that he will not support a Scalia replacement this year. 

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