JD Vance, the Republican vice-presidential candidate, has sparked both praise and warnings following his recent debate performance. While his post-debate momentum has solidified his standing among supporters of former President Donald Trump, he faces sharp criticism from those concerned about his political positions, particularly from Trump's own family.

In a Thursday newsletter, Mary Trump, the niece of former President Donald Trump, issued a stark warning about Vance, describing him as "vile, creepy, cruel, and violent." She expressed deep concern about the possibility of Vance becoming president if Trump wins the 2024 election and is unable to serve his full term. "Forty-year-old Vance is also a fascist, and if Donald gets back into the White House, he will almost certainly become president at some point during the next term," she wrote.

Mary Trump's sharp criticism comes on the heels of a vice-presidential debate between Vance and Minnesota Governor Tim Walz. The debate was marked by sharp ideological differences, and Vance's performance earned praise from many on the right. In particular, former President Trump was reportedly "absolutely thrilled" with Vance's debate showing.

However, Mary Trump is not alone in her concerns about the Ohio senator. Vance has long faced criticism for his views on women, including remarks from a 2021 interview in which he criticized what he referred to as "childless cat ladies" - a comment that drew backlash from figures such as Taylor Swift and Jennifer Aniston. Mary Trump called Vance "a notorious misogynist who hates women in a way that is deep and multi-faceted."

Despite these concerns, post-debate polling indicates that Vance's favorability ratings have surged. Before the debate, he was one of the most unpopular vice-presidential candidates in American history, with just 30% of Americans viewing him favorably. After the debate, that number jumped by 11 points to 41%, according to CBS and YouGov polling. Vance's opponent, Governor Walz, also saw a boost in his favorability, rising from 52% to 60%.

While these figures suggest Vance's debate performance has resonated with some voters, political commentators are divided on whether it will impact the broader election outcome. Former Trump White House communications director Alyssa Farah Griffin noted that Vance's performance likely won't change the result of the 2024 election, but she believes it solidifies his role as a key figure in the future of the MAGA movement.

"JD Vance is a significantly more eloquent Donald Trump," Griffin remarked during CNN's post-debate analysis. "I don't agree with JD Vance on quite a bit, but he speaks to MAGA in a way that he comes off as an incredibly effective communicator."

Griffin, who resigned from her White House role in December 2020 and later became an outspoken critic of Trump following the events of January 6, 2021, pointed out the conflicting elements of Vance's persona. "JD Vance is a chameleon," she said, describing him as a politician with multiple sides - one of which is his "mean-spirited internet troll" side, referring to his often provocative social media presence.

Griffin acknowledged that while Vance made some misleading statements during the debate, he managed to convey a level of empathy that made him appear convincing. "He tried to show the side of empathy with him that I found myself believing it," she said. But Griffin quickly added that Vance's debate rhetoric cannot be viewed in isolation. "Then I remember his lies about Haitian kids, his comments about childless cat ladies, and his general record online."

As post-debate polling shows a narrow edge for Vance, the debate has further solidified his standing with Trump's base, marking him as a key figure in the post-Trump Republican landscape. However, Mary Trump's warning underlines the deep divisions within the Republican Party over Vance's rise. While his political future looks brighter, the criticisms about his past statements and his aggressive rhetoric remain a point of contention.