A Texas-based power company that only joined the S & P 500 two months ago is the third-best performing stock in the index this year, boosted by the same demand for everything connected to artificial intelligence. Fast forward to today and Vistra stock has soared 139% this year, adding $18.5 billion to its market cap, which now totals $32 billion, according to FactSet data. "We are always surprised when you see a move the size that we've seen, but I think it's been a long time building," Jim Burke, CEO of Vistra, told CNBC's "Closing Bell" Tuesday. Vistra also owns nuclear power plants, one of the most in-demand power sources in the 2024 market because reactors burn no fossil fuel and emit no greenhouse gases . Guggenheim has a buy rating on Vistra stock with a price target of $133, implying 44% upside from Wednesday's close of $92.31.

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Persons: Jim Burke, CNBC's, we've, Burke, Vistra, Shahriar Pourreza, Pourreza, they'll, Guggenheim, Vistra hasn't, Mark Nelson, Joseph Dominguez, Constellation's, aren't Organizations: Vistra Corp, Texas Utilities Co, Dynegy Inc, Computer, Nvidia, Nuclear, Guggenheim Securities, Energy, Guggenheim, CNBC, Amazon Web Services, Talen Energy, Constellation Energy, Wall Street, Radiant Energy, Constellation Locations: Texas, Irving , Texas, Dallas, Ohio, Pennsylvania, Energy Harbor, U.S, East Coast