By GRETCHEN PARKERAssociated Press Writer BALTIMORE (AP) – Kweisi Mfume, a former five-term U.S. congressman who stepped down to become president of the NAACP, launched an 18-month campaign Monday to win Maryland’s open U.S. Senate seat. The 56-year-old Baltimore native and former radio talk show host stood at a podium backed by half-dozen American flags as he declared in a booming voice: “I can’t be bought, I won’t be intimidated, and I don’t know how to quit.” Mfume had made no secret that his sights were set on a U.S. Senate seat. But he waited for his ally Paul Sarbanes, the five-term incumbent, to decide whether to stay or go. Sarbanes, 72, announced Friday he would not seek another term, and within two days Mfume let others in the Democratic party know his intentions. He called Baltimore Mayor Martin O’Malley, a likely Democratic candidate for governor who also has not ruled out running for Sarbanes’ seat, on Sunday night. Mfume said he also plans to speak with Democratic U.S. Rep. Dutch Ruppersberger, one of three Maryland congressmen who has not ruled out running for the seat. Rep. Chris Van Hollen told The Associated Press he is putting together an exploratory committee to examine his prospects and Rep. Benjamin Cardin also has been mentioned as a possible candidate. U.S. Rep. Al Wynn officially bowed out of the race, making his announcement just two hours after Mfume’s news conference Monday. Mfume said he wanted to make his ambitions known and not “play games” or waste time by further investigating his chances in winning the seat. He said in November, when he stepped down from the NAACP, that he was considering a Senate bid. “I hope this early statement says to people I’m very serious about this. I’m in this for the long haul,” Mfume said, surrounded by five of his six sons and about a hundred supporters in a conference room overlooking Baltimore’s Camden Yards stadium. Mfume already has a strong base with black voters, who generally make up at least 30 percent of the electorate in Maryland’s Democratic primaries, said Annapolis-based pollster Patrick Gonzales. “This is step one in what will be an embarrassment of wealth for the Democratic Party in 2006,” said Derek Walker, spokesman for the Maryland Democratic Party. “Most states have the problem of ‘Let’s beg someone to get in the race, let’s dangle some carrot out there.’ In Maryland, we don’t need to beg anyone.” Mfume, 56, left the House in 1996 to take the NAACP post. At the time, the Baltimore-based civil rights group was in turmoil _ rocked by an embarrassing sex scandal involving its previous head, bitter internal strife and a crippling $3.2 million deficit. Many observers say Mfume brought credibility and stability, working to institute corporate style-management practices. When he stepped down in November, the organization had enjoyed a budget surplus for eight consecutive years and an increasing endowment fund. Mfume said Monday his decision was not made out of “any misguided sense of ego or entitlement.” Instead, Mfume says he is making his announcement with the belief that “there are still among us men and women who believe that the real power of government” is its ability to empower citizens to improve their lot and their futures. He pitched himself as a hard worker, raised in poverty, who conducts himself as a straight shooter — “direct on the things I believe in and willing to listen and learn more about the things that I don’t” — and he pledged to run a campaign that speaks to Marylanders and “not at them.” Mfume said he’s not afraid to go on the record as a “social liberal”, although he considers himself a fiscal conservative. Democrats outnumber Republicans in Maryland 2-to-1, but the state elected a GOP governor in 2002 for the first time in 36 years. If Maryland voters consider Mfume too liberal, they’ll let him know, he said. “I’ll be in their communities. I’ll be in their neighborhoods,” Mfume said. “I know people will measure me based on what they see, from this point on.” Mfume said his campaign will focus on public education and its need for advocates and parental involvement, rising health care costs, the need for a strong military defense of the United States. Also, he said, “It is in the United States Senate where we need uncompromised and disciplined leadership on the issue of Social Security reform, job creation, small business development and economic assistance to states.” Mfume, whose adopted West African name translates to “conquering son of kings,” began his career as a dashiki-clad radio talk show host and political activist in the 1970s.