Byron York of the Washington Examiner identifies a key challenge for Democratic presidential candidates.

The president’s Democratic 2020 challengers face a daunting problem: Unless there is a serious economic downturn, the answer to the are-you-better-off question will work in the president’s favor, not his opponent’s.

The unemployment rate, 3.7%, is the lowest it has been in half a century. June’s employment report — 224,000 new jobs — brought another strong performance. The economy is growing at a slightly better than 3% annual rate. Most importantly, in the context of an election, wages have grown 3.1% over last year with low inflation, improvement that has not been seen in years.

Any analysis of the 2020 election should include the warning that things could change. But barring a significant reversal, in 2020 most voters would likely answer yes when asked if they are better off than they were four years ago. And then they would vote to reelect the incumbent president.

That leaves Democrats with the task of convincing millions of Americans to vote against their economic interests, to choose a Democrat over the president, during a time of economic satisfaction.

How to do it? Some Democrats have chosen to argue that there is something so wrong with the president, that he’s a racist, or he is an agent or Russia, or he is something equally terrible, that the traditional measures of a successful presidency do not apply. …

… Together, the message could be characterized as: Yes, the economy is growing, unemployment is low, and wages are rising. But America under a reelected Donald Trump would become a racist dystopia in which all the beliefs Americans hold near and dear would be under constant siege. How could any decent person vote to reelect the president?