Updated: 5:04 p.m.

Sen.-elect Scott Brown (R-Mass.) will be sworn in to office on Thursday at 5 p.m.

“The certification will be coming in Thursday morning, and the swearing-in will happen Thursday evening,” a GOP leadership aide said.

Brown’s campaign counsel, Daniel Winslow, delivered a letter requesting “immediate certification of his election results” on Wednesday to Massachusetts Gov. Deval Patrick (D) and Secretary of State William Galvin, according to a release. Brown was elected on Jan. 19 to the seat held by the late Sen. Edward Kennedy (D-Mass.), a victory that shattered the Democrats’ 60-seat supermajority and gave the Republicans the power to filibuster.

“While Sen.-elect Brown had tentatively planned to be sworn into office on Feb. 11, he has been advised that there are a number of votes scheduled prior to that date,” Winslow wrote in the letter. “For that reason, he wants certification to occur immediately. As he is a duly elected U.S. Senator from the Commonwealth of Massachusetts, he is entitled to be seated now.”

A Patrick spokesman confirmed that Brown’s paperwork would likely be certified Thursday.

“As the lieutenant governor stated earlier today, the governor will convene the Governor’s Council at 9:30 a.m. tomorrow morning and certify the results,” spokesman Kyle Sullivan said. “This will ensure that Sen.-elect Brown’s request to receive the final paperwork by 11 a.m. tomorrow is fulfilled.”