Everyone knows that President Donald Trump takes a different view of immigration than George W. Bush did. The shift among Democrats gets less attention but is no less real, as I write in Bloomberg Opinion:

As is often the case, the evolution of Democratic attitudes can also be seen by tracking Hillary Clinton’s comments over the years. When she first ran for president, from 2006 through 2008, she was careful to take a moderate tack. She opposed giving driver’s licenses to illegal immigrants, came out for “tougher employer sanctions” to deter the hiring of illegal immigrants, and toggled between calling them “illegal” and “undocumented” immigrants.
During her second run, under pressure from Bernie Sanders, she came out for driver’s licenses and apologized for using the term “illegal immigrants.” Talk of employer sanctions fell away. (Sanders himself, by the way, has also “evolved” on immigration.)

The Democratic shift, I go on to argue, created a political opportunity for Republicans, who could either lower the costs of their own departures from the views of middle-of-the-road voters or take the center ground on the issue away from Democrats.