First Lady Michelle Obama is set to take the stage at the Democratic National Convention Tuesday to make the case for why her husband deserves another four years in the White House.

Mrs. Obama will also spend time shoring up support among key constituencies.

She will speak to the party's African-American, Hispanic, and women's caucuses.

The first lady will also address a gay and lesbian luncheon.

Meanwhile, Democrats will vote to adopt their party platform today.

The platform was revealed last week. It calls for higher taxes on wealthier Americans, and it backs same-sex marriage and abortion.