The struggle to replace an 18-term congressman, Rep. Charles Rangel of Harlem, could be a political brawl like none other in recent memory, pitting one man who said he “loves” the congressman against another who says he thinks Mr. Rangel stole the seat 36 years ago, as well as a host of other Democrats who have quietly waited for such a chance.

“I love the man, personally and politically,” Assemblyman Keith Wright said when asked about Mr. Rangel, who was first elected to Congress in 1970.

“When I refer to 1970, I say Rangel replaced my father. He never defeated him,” Assemblyman Adam Clayton Powell IV, who wants to reclaim the seat, said.

More than half a dozen elected officials and community activists are said to be eyeing the seat held by Mr. Rangel, who declined to say whether he would serve a full, two-year term if Democrats fail to take back the House in the midterm elections this November.

“I think that would be left up to my community and my political advisers in terms of who would succeed me and what’s the best way to have a transition,” Mr. Rangel said when asked by The New York Sun if he would serve a full term in a Republican-led House. Mr. Rangel did not return messages left at his office Thursday seeking clarification.

Political insiders say the field of candidates includes, but is not limited to, Messrs. Wright and Powell, their Assembly colleague Adriano Espaillat, City Council members Inez Dickens and Robert Jackson, a former council member, Bill Perkins, a former president of Manhattan, C. Virginia Fields, and the Reverend Calvin Butts.

The timing of Mr. Rangel’s departure could affect who runs to replace him.

In Brooklyn, Rep. Major Owens announced in late 2003 that he would not seek re-election in 2006. That led to a heated re-election for the 22-year incumbent in 2004 and a protracted fight for his seat this year. Of the five Democrats who entered the race, four remain.

When Rep. Thomas Manton of Queens retired in 1998, he announced it quietly after circulating petitions for re-election. On the last legal day to find a replacement, Mr. Manton convened a small meeting and telephoned Joseph Crowley, then an Assemblyman, to tell him he would be on the ballot in November as a congressional candidate.

Should Mr. Rangel resign from Congress mid-way through his term, Democratic leaders, not voters, would pick the party’s nominee, an election lawyer, Martin Connor, said.

“The committee that would nominate the candidate consists of the party chairs of each county the district has a portion of,” Mr. Connor, who also is a state senator of Brooklyn, said. A spokesman for the New York State Democratic Committee confirmed the process.

Mr. Rangel’s district is centered in Harlem, but stretches from Manhattan’s West Side and includes portions of the Bronx and Queens.

Most of the potential candidates said they were patient, despite Mr. Rangel’s latest remarks.”I wouldn’t make a call on it until he makes a decision to stay or to go,” Mr. Espaillat said. “I don’t see a swelling of support for him to step down.”

“As long as Charlie is there, I fully support him,” Ms. Fields, a 2005 mayoral candidate, said. “If there becomes a vacancy, I am open to looking at that seat.”

The chief of staff to Mr. Jackson, Susan Russell, said he “isn’t interested in answering a question that would create speculation and distraction from the work that we’re currently doing.”

Mr. Butts said he was interested in Mr. Rangel’s seat, but “I don’t want to be in a dog fight with a lot of other possible pretenders to the seat.”

When asked about a possible congressional race, Mr. Perkins said,”I don’t even know where that question is coming from.” He is running for the state Senate seat being vacated by David Paterson, who is running for lieutenant governor.

“If you don’t think he’ll have something to say or something to do with who replaces him, you’re not as informed,” Mr. Wright said. “Anyone in politics who is not interested in becoming a Congress member needs to have their head examined.”