Updated: 6:20 p.m.

Sen. Scott Brown (R-Mass.) was sworn in Thursday, officially becoming the GOP’s 41st vote and giving the minority the power of the filibuster.

“I’ll be the 41st vote. I won’t be the 60th vote,” said Brown, when asked at a news conference following his swearing-in if he might serve as a crucial moderate vote for Democrats on various issues.

“I’m hopeful there will be bipartisan negotiations, that’s part of the
problem,” Brown added, denouncing partisan fights and backroom deal-making.

Nearly three-dozen Members sat in the Senate chamber to watch Brown take the oath of office over a pair of his daughters’ bibles. He chatted with Sen. John Kerry (D), his new home-state colleage, and outgoing Sen. Paul Kirk (D), who was appointed to the seat in September following the death of Sen. Edward Kennedy (D). Brown, a social moderate, is the first Republican elected to the Senate from Massachusetts in more than three decades.

Brown arrived in Washington, D.C., just hours after the necessary paperwork was certified by Massachusetts Gov. Deval Patrick (D). Though Brown had originally planned to be sworn in on Feb. 11, he pushed the date up by a week to begin voting on President Barack Obama’s executive branch nominees and other matters.

“I want to get to work,” Brown said. “I think it’s important to first look at jobs and job creation, terrorism and taxation.”

Senate Republicans were jubilant in welcoming their newest Member.

“I look forward to working with him to achieve real reforms across the board — from reining in wasteful spending to protecting our nation from terrorists and bringing down health care costs for all Americans,” said National Republican Senatorial Committee Chairman John Cornyn (Texas).

In a floor statement earlier Thursday, Minority Leader Mitch McConnell (R-Ky.) said: “The people of Massachusetts are eager to have Sen. Brown working on their behalf, and Republicans look forward to having him join our conference.”

“This was a high-profile election. Now it’s time to get to work,” McConnell added.