UPDATED 02/24/11 2 p.m.

CHICAGO (CBS) — Illinois State Senate Assistant Majority Leader Rickey Hendon (D-Chicago) has resigned from his seat.

“Today is a wonderful day, and as much as I have enjoyed working with you and all of my fellow Senators, I have decided to call it a day and retire from this wonderful institution,” Hendon wrote in his resignation letter.

He asked supporters to “accept my decision and allow me to move on with my life,” but did not specify further why he had decided to resign.

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Read The Letter Here

Alderman Walter Burnett – a former political opponent — said he talked to Hendon and said Hendon was upset that his ally, Patricia Horton, did not win the city clerk’s job.

“[She] didn’t get as many African American votes as he expected her to get in the African American community. He found this to be humiliating and he said he’s out of it,” Burnett said.

“I said, ‘Well, are you going to another position? Are you going to another job?’ He said no, he’s done with politics. Period.”

Hendon has served his West Side district in the state Senate for five terms. He was elected to the seat in 1992.

In the fall, records showed a federal grand jury had demanded documents on Illinois state grants, including some that went to groups with ties to Hendon. But Hendon was not accused of any wrongdoing.

Hendon briefly mounted a candidacy for mayor last fall, after Mayor Richard M. Daley announced his plans to retire. Among his stated goals had been to reopen Meigs Field, as part of a plan to bring more business to Chicago.

But a week after the grand jury investigation ended, Hendon withdrew from the race. He said the subpoenas had no impact, instead saying he believed his candidacy was “not worth causing disunity within the African-American community, or consternation from those who don’t really understand who Rickey Hendon is.”

A wide field of potential mayoral contenders was ultimately reduced to six. Rahm Emanuel was elected with 55 percent of the vote on Tuesday.

Hendon has also gained attention for some pointed comments directed at other lawmakers. In the fall, he drew headlines at a get-out-the-vote rally for Gov. Pat Quinn, for his remarks about state Sen. Bill Brady (R-Bloomington), who was challenging Quinn at the time.

Hendon called Brady an “idiotic, racist, sexist, homophobic person.”

Brady demanded an apology, but Hendon called his comments “necessary.” When Hendon later did apologize, Brady refused to accept it.

Hendon also made headlines during debate on the state’s civil unions bill in December, when he took issue with those who objected to the bill and to any same-sex unions on religious grounds.

“When I sit here and I hear adulterers, and womanizers, and folks on their wives, and down-low brothers say they’re going to vote against this bill, it turns my stomach, the hypocrisy dripping in this chamber right now. We know what you do at night and you know too,” Hendon said during the debate. “Why not call it like it is?” Just say you don’t like certain folk.”

Hendon is a native of Cleveland, Ohio, and grew up in Chicago and Detroit. He worked for Mayor Harold Washington in the 1980s, and served as Democratic committeeman of the Near West Side’s 27th Ward from 1988 until 1996. He was elected alderman of the ward in 1991, but left not long afterward when he was elected to the state senate.

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