Weeks before attorney general nominee Loretta Lynch appeared before the Judiciary Committee to testify, Sen. David Vitter (R-La.) had already announced he would vote against her to underscore his opposition to Obama’s executive action on immigration.

A coalition of civil rights leaders Monday sent Vitter a letter blasting him for “blatant political posturing.” The letter was signed by Marc Morial, president of the National Urban League and Wade Henderson, president of the Leadership Conference on Civil and Human Rights.

On the front of Vitter’s gubernatorial campaign Web site is a petition that says: “We’re opposed to amnesty and blocking your AG nominee.”

“Your use of this responsibility for political gain is shameless and leads us to question the integrity of your decisions. It appears that your overtly political action is connected to your effort to run for Governor of the State of Louisiana,” they wrote.

Asked about the letter, Vitter’s office referred us to his previous criticisms of Lynch. At her hearing on Jan. 28, he listed a series of grievances and noted they’d previously had a private meeting, but remained unsatisfied.

“As I told you in my office, like many, many citizens and members of the Senate, I have a huge concern regarding what I think is the president’s illegal, unconstitutional executive amnesty, and I have a huge concern of the fact that you think it is within the law,” Vitter said.

The civil rights leaders accused Vitter of “shameful abdication of your responsibility as a member of the Senate Judiciary Committee.”

The panel, which meets Thursday, is expected to delay her confirmation by a week or more.