Sen. John McCain's passing has left his Senate seat vacant and waiting to be filled by Arizona Gov. Doug Ducey, a Republican. If she's interested in filling that seat, Meghan McCain would deserve immediate support from conservatives. To be clear, Meghan McCain might not want to be a U.S. senator. And that's fine, no one should ever face pressure to serve in public office unless in the situation of a national emergency. But if McCain is open to replacing her father until a special election can be held in 2020, she would make a great conservative successor to her irreplaceable...