WASHINGTON, (Reuters) – Maxine Waters yesterday  became the second Democrat in the U.S. House of Representatives  in two weeks to be accused of ethics violations, an  embarrassing blow as the party fights to keep its majority in  the Nov. 2 elections.

The House ethics panel said it had found evidence of  undisclosed ethics violations against California’s Waters, who  denied breaking any rules and vowed to contest the allegations  in a public trial. “I simply will not be forced to admit to something I did  not do,” Waters said in a prepared statement.

The announcement came just days after the ethics panel  announced 13 ethics charges against New York Representative  Charles Rangel, whose trial is expected to begin in September.

Both Rangel and Waters are members of the Congressional  Black Caucus, making the cases highly sensitive as Democrats  are working to get a big voter turnout by African Americans,  one of their traditional constituencies.

The ethics charges were an embarrassment for Democrats, who  face substantial losses in the chamber in November and whose  leader, House Speaker Nancy Pelosi, had pledged to “drain the  swamp” of corruption resulting from a dozen years of Republican  domination that ended in 2006.