Vice President JD Vance’s presence at a closed-door donor summit this week intensified speculation about the 2028 presidential race, where he and Secretary of State Marco Rubio are viewed as leading contenders to succeed Donald Trump on top of the Republican party. On Monday at the Four Seasons in Nashville, Tennessee, Vance headlined a meeting of the Rockbridge Network, a donor group he helped establish in 2019 while working as a venture capitalist, according to CBS News. Roughly 250 members attended the political pow-wow, where tickets ran upwards of $100,000, an unnamed source told the outlet. The former Ohio senator and Hillbilly Elegy author spoke of his anti-fraud push and the looming midterm elections — while refraining from remarking on the 2028 presidential election. “It obviously wouldn’t be too smart to do that,” the source said. JD Vance and Marco Rubio are the front-runners to replace Trump in 2028, but only one of them attended a secret donor summit on Monday, according to a new report (Getty Images) Still, that didn’t deter deep-pocketed attendees — …