Jennifer Hudson broke the news to ET that she feels honored to sing the national anthem on the night Barack Obama accepts the nomination for president at the Democratic National Convention.

"This is definitely one of the biggest honors for me," the Oscar winner tells ET. "It's something that I've really wanted to do."

Hudson, who calls Barack a "great role model," adds that she has never yet sang for such a large crowd.

The singer and actress spoke to ET on the set of the Dove Campaign for Real Beauty and the Dove Self-Esteem Fund -- a cause Hudson champions because it tackles self-esteem issues and the pressures of body image.

The former "American Idol" contestant will release her self-titled debut album on Sept. 30. Watch ET for more with Jennifer Hudson!