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NEW ORLEANS -- Republican National Committee Chairman Michael Steele, who has come under fire for his lavish spending, told GOP activists Saturday that he has taken responsibility for his "mistakes" and is now ready to "move on."

In a speech to the Southern Republican Leadership Conference, Steele alluded to the controversy sparked by his committee paying a nearly $2,000 bill at a sex-themed nightclub in Los Angeles that led to at least one state party chairman calling for his resignation.

"Now I'll be the first to admit I've made mistakes and it's been incumbent on me to take responsibility, shoulder the burden, make necessary changes, and move. We've all had to do that from time to time," he said, drawing applause.

"But the one mistake we cannot make is to lose this November," he added.

The outspoken and flamboyant Steele has been a lightning rod for criticism since taking the job last year. But the criticism escalated after recent revelations of Steele spending thousands of dollars on private jets and the RNC picking up a $1,946 tab that a group of young Republicans ran at a risqué Los Angeles Voyeur nightclub on Jan. 31.

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The RNC fired a staffer it blamed for the outing and said the bill would be reimbursed by a donor who had attended. Steele also accepted the resignation this week of his chief of staff and allowed one of his senior advisers to leave in an attempt to reassure GOP donors upset about his leadership.

But that didn't stop Tom Fetzer, head of the North Carolina Republican Party , from calling on Steele to step down.

In a letter to Steele, Fetzer said the resignation is the only way to end scrutiny of the national party over lavish spending and ensure Republicans maximize gains during the mid-term elections.

"I believe that the best service you can render to your party at this critical juncture is to graciously step aside and allow the party to move on from this current quagmire," Fetzer wrote in the letter.

But Steele has said he would not resign and defends his stewardship of party affairs. He has dismissed criticism as griping by GOP figures uncomfortable with his "streetwise" managerial style.

The RNC has also issued a letter of support for Steele that 32 state party chairmen so far have signed, RNC spokesman Doug Heye told Fox News.

The letter states that the Republican Party state chairmen "believe Chairman Michael Steele can lead the RNC to be a full partner with us this fall in our efforts to fire Nancy Pelosi and win Republican majorities in Congress and among governors."

"The charge of any national chairman is to raise money and win elections," the letter reads. "With over $100 million raised, victories in Virginia, New Jersey and Massachusetts, and victories in 29 of 37 special elections, Michael Steele has demonstrated that under his chairmanship the RNC has the ability, focus, and drive to lead Republicans to a sweeping victory in November."