CLEAR LAKE, Iowa — Deidre DeJear is Iowa’s newest political star — even if she hasn’t yet won an election. Sen. Cory Booker of New Jersey, who is considering a bid for the Democratic presidential nomination, recently made his inaugural trip to Iowa by headlining a fundraiser for DeJear. Sen. Bernie Sanders of Vermont, who is considering a second White House run, will stump with DeJear on Sunday.