Matthew Dowd, the chief strategist for George W. Bush’s presidential reelection campaign who later split with the former president publicly, is running for lieutenant governor as a Democrat. Dowd also has worked for Bob Bullock, who in 1994 was the last Democrat elected as Texas lieutenant governor, and faces an uphill battle to unseat Republican Dan Patrick, the state’s second-highest-ranking official who has steered Texas politics into the far-right fringes of the GOP...