When Marco Rubio during Thursday’s Republican debate accused his rival candidate Chris Christie of backing Sonia Sotomayor’s appointment to the Supreme Court in 2009, the New Jersey governor was indignant, exclaiming, “First of all, I didn’t support Sonia Sotomayor.”

But the record says otherwise.

On July 17, 2009, Christie, who was then running against incumbent New Jersey Gov. Jon Corzine, issued a statement praising President Obama’s nominee for her “capability, competence and ability” and urging the Senate to confirm her.

“After watching and listening to Judge Sotomayor’s performance at the confirmation hearings this week, I am confident that she is qualified for the position of Associate Justice for the U.S. Supreme Court,” Christie said in the statement.

So how could Christie claim in Thursday night’s debate that he had never supported Sotomayor? His campaign points to an attack from New Jersey Democrats dated July 13, 2009. It accused Christie of taking a “hard-line stance” against Sotomayor, citing his comment in a Republican primary debate that Sotomayor “wouldn’t have been my choice” for the court.

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It’s easy to see what was going on here. New Jersey is a deeply blue state, one that Barack Obama had carried by 16 points the year before Christie set out to run for governor. At the start of the 2009 campaign, in fact, Republicans had won just four statewide elections in New Jersey in the previous 37 years – three of them by less than a point. So even though Corzine was deeply unpopular, Christie still faced an uphill battle. His biggest obstacle was his party affiliation, and Christie was just as eager to play down his ties to the national GOP as Democrats were to play it up.

Close video Christie: Rubio can't even look me in the eye New Jersey Gov. Chris Christie joins Morning Joe to discuss his debate performance Thursday night in North Charleston, South Carolina. Christie also discusses entitlement reform, Planned Parenthood, if he supported Sonia Sotomayor, wage growth and… New Jersey Gov. Chris Christie joins Morning Joe to discuss his debate performance Thursday night in North Charleston, South Carolina. Christie also discusses entitlement reform, Planned Parenthood, if he supported Sonia Sotomayor, wage growth and… share tweet email Embed

Sotomayor’s nomination had put Christie in a bind. President Obama picked her in the final days of the GOP gubernatorial primary, where Christie was facing a stubborn challenge from a conservative insurgent. And so Christie had assured Republicans that Sotomayor was “not my kind of judge.” But then, once Christie won the primary, Democrats sought to make that comment an issue.

“It is appalling,” New Jersey’s Democratic state chairman said on July 13, “that despite her vast experience and unquestionable qualifications … Christie would align himself with right wing conservatives like Rush Limbaugh and Newt Gingrich in rejecting Judge Sotomayor, the first Latina nominated to the highest court in the nation, without as much as an explanation beyond tersely dismissing her as ‘not my kind of judge.’”

It was then that Christie issued his statement of support for Sotomayor. Yes, he acknowledged, Sotomayor wouldn’t have been my pick, but “President Obama has used his opportunity to fill a seat on the Supreme Court by choosing a nominee who has more than proven her capability competence and ability.

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“I support her appointment to the Supreme Court and urge the Senate to keep politics out of the process and confirm her nomination.”

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Christie, meanwhile, went on to defeat Corzine by four points that November. But now, seven years later, it’s not New Jersey’s moderate-to-liberal swing voters that he’s targeting – it’s conservative Republicans in Iowa, New Hampshire and South Carolina.

Weeks later, Sotomayor was confirmed by the Senate by a 68-31 vote. All of the No votes came from Republicans.

It’s not a convenient fact for Chris Christie these days, but it is a fact: He supported Sonia Sotomayor’s nomination for the Supreme Court.