Donald Trump
Trump was also accused of telling complainant "you could do some damage," referring to her looks. He told the New York Times: "That's not in my vocabulary."Getty Images

Donald Trump's campaign paid male staff members more then women, and wouldn't allow women to plan or speak at rallies, according to a sex discrimination complaint filed in Iowa. Elizabeth Mae Davidson, 26, was a paid organiser for the Trump campaign in Davenport, Iowa's third-largest city.

She filed her complaint with the Davenport Civil Rights Commission, the New York Times reported. When Davidson, 26, and another young woman first met Trump at a rally before she was hired, he told them, "You guys could do a lot of damage," referring to their looks, she complained.

Trump denied to Bloomberg Politics that he made the comment, but didn't discuss the other issues. "It's just not something that's in my vocabulary — not that it's the worst thing I've ever heard," Trump said, referring to the "damage" comment.

He said he didn't know Davidson but that "my people tell me she did a terrible job" and was recently fired. He also said he had heard "strange" things about her. "She goes around dressing like Melania, my wife," he added.

He complained to the Times about running the story the day before the Iowa caucus, saying: "A story like this could damage my chances." Trump has been criticised for sexism after using the word "bimbo" to refer to Fox News commentator Megyn Kelly.

Trump skipped the last GOP debate insisting that Kelly had it in for him when he was asked at an earlier debate if he thought he could count on female votes after referring to women as "fat pigs," "dogs" and "slobs."

US election 2016: Guide to the Republican candidatesIBTimes UK

Davidson opened the second field office in Iowa for the campaign and was described in a recent Times article as being one of the campaign's most effective organisers. But the article also spoke of poor management of the campaign by senior organisers. Davidson was fired shortly after the story for making "disparaging comments about senior campaign leaders," which she denied, and of breaking a non-disclosure agreement. Male campaign workers who also spoke to the Times weren't fired.

Davidson said she was paid $2,000 a month while several men holding the same job were paid up to $4,000, according to public records.

In the complaint, Davidson said that the alleged discrimination caused her to have "suffered lost wages, mental anguish and damage to my career." Davidson is the daughter of Judy Davidson, the Republican chairwoman of Scott County in Iowa.