NEW ORLEANS — A comedian impersonating President Obama who was hired to perform here on Saturday at the Republican Leadership Conference delivered racially tinged remarks about Mr. Obama’s heritage and offered a mocking assessment of the Republican presidential candidates.

The impersonator, Reggie Brown of Chicago, opened his act by joking about Mr. Obama’s family history, referring to his white mother from Kansas and his black father from Kenya. He said that he was born in Hawaii, adding, “or as the Tea Partiers like to call it, Kenya.”

He said that Michelle Obama, the first lady, enjoys celebrating all of February, Black History Month. He said the president celebrates only half the month.

“My mother loved a black man and, no, she was not a Kardashian,” Mr. Brown said later, referring to the family that stars in reality shows. Khloe Kardashian, who is white, is married to Lamar Odom, who is black and plays for the Los Angeles Lakers.

The audience, which was nearly entirely white, watched with befuddlement as the impersonator told them to look into the future to see what the Obamas will look like when they are retired. An image of a feuding husband and wife, from the TV show “Sanford and Son,” was flashed on screens in the ballroom.

The Louisiana Republican Party hired Mr. Brown, who has spent years refining his impression of Mr. Obama, to appear during the afternoon session of the party’s three-day gathering. He also made derogatory jokes about Mitt Romney, Tim Pawlenty and Newt Gingrich before his hosts cut him off with loud music and escorted him from the stage before his act was over.

The act, which included a fake Secret Service detail, a recorded video address from the Oval Office and a presidential seal, came one day after Govs. Haley Barbour of Mississippi and Bobby Jindal of Louisiana urged fellow Republicans to stay disciplined — and focused on economic issues — in their quest to defeat Mr. Obama next year.

The act included photographs of Anthony D. Weiner, a Democrat who resigned his seat in Congress because of lewd pictures he sent to some of his Twitter followers. Then, the impersonator turned to the implosion of Mr. Gingrich’s campaign, after many of his aides resigned 10 days ago, saying, “His supporters are dropping faster than Anthony Weiner’s pants.”

Taking aim at Mr. Pawlenty, a former Minnesota governor, Mr. Brown mocked his performance in a debate last week in which he softened his criticism of the health care plan that Mr. Romney had signed into law in Massachusetts.

He said Mr. Pawlenty missed the event because he was “having his foot surgically removed from his mouth.” He added: “Don’t worry. It’s covered under Obamneycare. Along with spinal transplants.” The impersonator also made an issue of Mr. Romney’s Mormon faith, referring to polygamy and showing a picture of a man with multiple wives.

Doug Heye, a party strategist and former communications director for the Republican National Committee, criticized the hiring of Mr. Brown. As word of the performance began to spread online, he wrote in a message on Twitter: “Wonder why many minorities have problems with G.O.P.? Our own fault.”