BOSTON -- Another candidate for January's special election to fill Sen. Edward Kennedy's seat in Washington announced his bid Thursday.

Boston Celtic's co-owner Stephen Pagliuca made the announcement at the TD Garden. He said that he was resigning from all the corporate boards he sits to avoid any conflict of interest.

"I am well aware that I am pursuing the office held by the greatest senator in the history of this commonwealth," he said. "He is the best."

Pagliuca recently announced he and a group of Boston businessmen are dropping their bid to buy the Boston Globe. But money won't be a problem for Pagliuca, whose estimated worth is about $400 million. He launches his first TV ad on Friday.

He already has a political team in place, including Gov. Deval Patrick's former chief of staff, and he is expected to launch expensive TV ads within a few days to introduce himself to voters.

The primary is less than 12 weeks away, but Pagliuca does have a small base of support to start this campaign.

"I think it is great. I think it is something he has a passion for," Boston Celtics Coach Doc Rivers said.

Pagliuca is managing director of Bain Capital, and has supported Republican candidates in the past.

"You have to treat your friends and be loyal to your friends, but my record will show 10 times the amount has been given to Democrats. I have Democratic values, and I did something for a friend."

He joins Democrats Attorney General Martha Coakley and U.S. Rep. Michael Capuano, who said he's declaring his candidacy on Friday.

On the Republican side, state Sen. Scott Brown and Canton Selectman Bob Burr are seeking the nomination.

"They have experience in politics. I have experience in business. What I don't like is 10 percent unemployment, lack of investment and we really don’t have anyone who has on the ground business experience," Pagliuca said.