For the past few weeks, Republican campaign professionals and conservatives who are seeing the GOP nomination heading into Donald Trump’s hands have been counseling anti-Trump voters not to panic and consoling themselves with the notion that things will turn around for Ted Cruz when the final weeks of the campaign shift to the Midwest and mountain states. After Trump’s astounding five-for-five primary night, by margins that were likely surprising even for Trump fans, it’s now Indiana or bust. If Trump wins the primary next week in the Hoosier State, Cruz is toast and Trump will almost certainly be the Republican...