In an era of celebrity tech entrepreneurs, Chicago has its own local star in Rishi Shah, a charismatic 31-year-old who has parlayed his advertising startup into connections with political and financial heavyweights.

A major donor to the Democratic Party, Mr. Shah has recently held private meetings at his office with Sens. Chuck Schumer and Elizabeth Warren. Fortune named him to its “40 Under 40” list. Forbes crowned him one of the world’s newest billionaires.

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