NEW YORK- Hillary Clinton cast herself as a champion for everyday Americans on Sunday, kicking off her long-awaited second run for the White House with a vow to fight for a level playing field for those recovering from tough economic times.

Clinton, who begins the 2016 presidential race as a commanding Democratic front runner, entered the fray with a video announcement in which she said the economic deck was still stacked for those at the top.

"Everyday Americans need a champion, and I want to be that champion," she said in the video, which was posted on her new website on Sunday afternoon. "So you can do more than just get by, you can get ahead. And stay ahead."

Clinton, who lost a bruising Democratic nominating battle to Barack Obama in 2008, said in a tweet that she would be traveling to Iowa, the state that holds the kickoff contest in the parties' nominating process in early 2016.

Clinton's campaign will emphasize her plans to address economic inequality and will tout the historic nature of her effort to become the first woman U.S. president, aides said. One of the biggest challenges for a woman who has been one of the most famous figures in the United States since the early 1990s, will be to show a more down-to-earth side while connecting with ordinary voters.

Critics, including liberals in her own party, say she has grown out of touch after decades as the wife of former President Bill Clinton, a U.S. senator and secretary of state.