Washington — The Senate Judiciary Committee on Tuesday postponed a planned vote on President Trump's nominee for attorney general, William Barr. Democrats have raised concerns that he may limit the scope of special counsel Robert Mueller's investigation into Russian meddling in U.S. elections.

The committee had planned to vote on Barr's nomination on Tuesday, but Republican Sen. Lindsey Graham, the new chairman, said the vote will now take place on Feb. 5. Delaying the committee vote has become standard practice for high-profile nominees.

If confirmed, Barr will assume oversight of Mueller's far-reaching investigation, which is also probing possible coordination between Trump campaign associates and the Kremlin. Since the president announced Barr's nomination in early December, Democratic lawmakers have raised doubts about Barr's ability to remain neutral while overseeing the investigation.

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Barr has been critical of the Mueller probe in the past. Last year, he wrote a memo to Deputy Attorney General Rod Rosenstein in which he argued Mr. Trump should not be forced to submit to questioning by the special counsel because "Mueller's obstruction theory is fatally misconceived" and based "on a novel and insupportable reading of the law."

During his confirmation hearing two weeks ago, he assured senators of his independence and said he would not be bullied by anyone into doing something he believes is wrong if he takes the helm of the Justice Department. Barr, however, did suggest he may not release Mueller's final report to the public because of an agency guideline.

Barr also said he agreed with longstanding Justice Department protocol that says presidents can't be indicted while in office.

Acting Attorney General Matthew Whitaker said Monday that Mueller's probe is "close to being completed."

John Nolen contributed to this report.