Sydney Leathers, the woman who derailed Anthony Weiner's once-promising New York City mayoral campaign by revealing he had sent lewd messages to her online, wreaked havoc on his election night plans as Weiner's campaign struggled toward the finish line.

Leathers appeared at Weiner's election night party at a restaurant in midtown Manhattan Tuesday night, clad in a low-cut red dress and blocking the entrance to the restaurant. Leathers seemed intent on confronting the man whose political comeback she says she ruined.

When Leathers was asked why she was outside Weiner's primary party she replied, "I just felt like I should. I felt obligated after being this involved in the situation," she answered.

"I was shocked that he was so high in the polls before the scandal happened. It was shocking to me, knowing the type of person he is," she added. "He tried to lie about the second scandal and tried to act as if the first scandal was the only thing that ever happened, that he had done wrong and he was this changed man and that's not the case and I am proof of that."

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Leathers' presence delayed Weiner's concession speech for more than a half hour, as he was forced to scurry in unceremoniously through a neighboring fast food restaurant in order to avoid a confrontation.

It was the second time in a day Leathers caused a headache for the Weiner campaign. Earlier Tuesday, Leathers was spotted outside of his Manhattan campaign headquarters holding an anti-Weiner sign. Weiner had been scheduled to conduct some phone calls there, but his campaign abruptly changed plans.

"I'm outside of Weiner headquarters just as a reminder of his impulse control problems and why he shouldn't be mayor. I'm a physical reminder of that," Leathers said. "I just felt that it was necessary for me to be here as a reminder of why the people of New York shouldn't vote for him and shouldn't take him seriously, unless they want a mayor 'Carlos Danger.'"

Weiner's wife Huma Abedin, who spoke emotionally on her husband's behalf at a press conference when the scandal broke, was not by his side as he conceded defeat, or as he cast his vote earlier in the morning. According to Weiner, the couple had originally planned on voting together.

"She's on a call. She will be voting today also," Weiner said. "She was in Washington late into the night. She's got some meetings and some calls and some stuff she's working on too. She's got her own busy thing going on."

Abedin, a top adviser to Hillary Clinton, was not seen on the campaign trail since speaking out in support of her husband when the scandal broke.