With the stunning Democratic upset in Wisconsin Senate District 10, this is a good time to take a look at just how fragile Trump's political coalition is. Start with the uncontroversial assertion that, while his victory in 2016 was astonishing and unexpected, it was not a robust victory. He lost the popular vote and without a massive swing in his favor among white noncollege voters, especially in key Rustbelt states (like Wisconsin!) he would not have won the electoral vote either.
In short, he barely squeaked through, a fact not lost on GOP strategists, even if Trump himself seemed delusional about this. Looking forward, GOP strategists knew something had to change to consolidate Trump's and the party's position. The 2016 election was so close that, without improvement, simply replicating 2016 performance in 2020 was likely to be a losing proposition due to ongoing demographic change that will affect even slow growth Rustbelt states. (The States of Change project will examine this and many other scenarios in a report and conference forthcoming in April.) Clearly a situation so precarious was not acceptable to non-delusional strategists.
There seemed little likelihood that the needed improvements would come from minority voters, where the GOP was lucky to do as well as it did in 2016. The Trump administration's first year provides no reason to change that judgement.
The default strategy seemed to be, under the assumption that holding Trump's white noncollege support would not be difficult, to make progress among white college graduates, viewed as the soft underbelly of the Democratic coalition. After all, the reasoning went, it was not so long ago that white college graduates were a solidly Republican group and their relative affluence should make them susceptible to GOP appeals.
So how's that working out? An absolute disaster. In our CAP report on Voter Trends in 2016, we estimated that Clinton carried white college graduate voters in 2016 by 7 points. Every piece of evidence we have indicates that Trump and his party have gone seriously south with white college voters since the election. Most recently Ronald Brownstein reported on data from Survey Monkey's surveys of over 600,000 respondents in 2017. According to these data, Trump's net job approval (approval minus disapproval) among this group was -20. That's pretty bad and indicates considerable slippage since the election. Even discounting the swing this suggests quite considerably, a substantial margin shift of this nature, even if the GOP holds all its previous white noncollege support, would result in a wipeout in the electoral college, compounding Rustbelt losses with defeats in states like Arizona. (Again, more this and other scenarios in the April States of Change report.)
That Trump coalition is looking pretty shaky. But surely Trump can keep white noncollege support and even increase it. They love him, right? Well, maybe not as much as they once did. According to the same Survey Monkey data cited above, Trump's net approval among this group is running at +12. But this is a group he won by 31 points in 2016! Again, considerable slippage and, again, even discounting this slippage significantly and ignoring his likely losses among white college voters, this suggests a swing against the GOP more than sufficient to sink the GOP in 2020, losing key states in the Rustbelt, Florida and even Georgia (!)
All this makes it easier to understand how the GOP managed to just lose a heavily Trump-supporting, heavily white noncollege senate district in Wisconsin. It's not an outlier; it's the new normal.