Graham Platner, who is running for the Democratic nomination in Maine to challenge incumbent Republican Sen. Susan Collins, said that the most serious allegations made against him aren't true.

In an article on Thursday in the New York Times, several women who dated Platner in the past accused him of being intimidating and emotionally abusive. Hours after the article was published, Platner told Chris Hayes on MS NOW that some of the allegations are "simply not true" and "politically motivated." 

He said he's been upfront about some of the parts of the Times piece, which claim he wasn't a good boyfriend and abusing alcohol. These were, Platner said, during a "dark period" of his life after he came back from combat service. 

The Times report is based on interviews with more than two dozen people, including six women he previously dated. Some of the women described their experience positively, while others said Platner was "toxic" and engaged in "unsettling" behavior.