Oakland County has been the richest county in Michigan for the last few decades– and was solidly Republican turf even before that, when it was farm country.

Yet as times have changed, so have politics. White blue-collar workers who were once solidly Democratic voted heavily for Donald Trump two years ago, which is why he won Michigan and the White House. But Republicans have paid a price for that.  The difference between the parties isn’t just a matter of economics anymore, but socio-economics.

Affluent, educated people who used to be Republican, especially women, have big problems with candidates who deny climate change, support intolerance and want to take away the right to an abortion. That’s why no Republican candidate for President has carried Oakland County since 1992. Oakland voters aren’t automatically Democratic either.

Governor Rick Snyder easily won Oakland both times he ran. But Hillary Clinton won it by 55,000 votes, doing better than President Obama had in Oakland four years earlier.

That was the case even though she became the first Democrat since 1988 to lose the state. This would suggest that Michigan Attorney General Bill Schuette won’t do well in Oakland County. We won’t know for sure until two weeks from tonight, when the votes are counted.

But it’s also interesting what’s happening in Oakland below the national and statewide levels. Thirty years ago, you could count on Republicans to be automatic winners of all the elected countywide jobs, like prosecutor, treasurer, water commissioner and county clerk.

Today, all those posts are held by Democrats. Republicans now hold only the sheriff’s department, where longtime incumbent Mike Bouchard has had mainly token opposition, and the top job, where L. Brooks Patterson has been county executive for twenty-five years, and was country prosecutor for twenty years before that.

Patterson, who is 79 and in questionable health since a devastating car crash in 2012, is essentially a relic of a sometimes embarrassing past, when suburban politicians made points by bashing Detroit in terms that were thinly veiled racism.

Brooks, as everyone calls him, came to prominence as an attorney for an anti-school busing movement in 1971, and used that to win the prosecutor’s job the next year.

Less than five years ago, he was the subject of a national magazine profile in which he said, among other things, that Detroit should be treated like an Indian reservation,  that we should surround it with a fence and throw in blankets and corn.

This wasn’t new; he’s been saying that since at least 1975. Oakland voters have continued to elect him, not because of his increasingly embarrassing behavior, but because he has hired a fleet of experts and technocrats who have made sure county government runs well.

Patterson’s regime has also been brilliant at budgeting, and the county has remained affluent and has continued to provide top-notch services.

But there are clear indications the Patterson era is nearing its end. He managed only 53 percent of the vote two years ago against an underfunded opponent, and this term is widely expected to be his last.  Most observers think that after Brooks leaves — voluntarily or otherwise — – he’s likely to be replaced by a Democrat, quite possibly Treasurer Andy Meisner.

Nobody knows for sure, but it is clear that in many ways, the county executive has fallen out of step with the times. His idea of mass transit is, literally, to add another lane to I-75.

That’s not what millennials want. Oakland County is increasingly diverse, has more people now than nine states of the union do, and is a powerhouse economy in its own right. How it evolves over the next decade will be crucial for its future—and for that of Metro Detroit.