"These allegations are credible; they are numerous," Gillibrand said on CNN. "I've heard these women's testimony, and many of them are heartbreaking."
Gillibrand had previously called for Sen. Al Franken's resignation after he was accused of groping women. Gillibrand has also said former President Bill Clinton should have resigned over his affair with a White House intern.
If Trump does not resign, Gillibrand said Congress should investigate his behavior.
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