Michael Tanner of the Cato Institute devotes his latest National Review Online column to Donald Trump’s electoral prospects.

Donald Trump is basking in another big victory. … And there may never have been a campaign that bases so much of its reason for existence on “winning.”

Yet, consider that even as Trump wins a landslide victory among Republican primary voters in New York, his polling numbers for November continue to plummet. According to the RealClearPolitics average of the latest polls, Trump would lose to Hillary Clinton — perhaps the worst Democratic candidate since George McGovern — by more than 9 percentage points. His net favorability rating is now just above 40 percent. That’s not exactly the stuff of “winning.”

To the degree that Trump has a strategy — a debatable point — it appears to be to appeal to disaffected white working-class voters, the oft-discussed “Reagan Democrats.” Trump hopes that by getting these nominally Democratic voters to cross over in November, he can expand the electoral map into the Midwest and other traditionally blue areas. In addition, Trump hopes to attract the 4 to 5 million “missing” conservatives who supposedly abandoned Mitt Romney in 2012.

Unfortunately, as with so much about the Trump campaign, the numbers don’t actually add up. …

… [I]f there is no certainty of a hidden pool of conservative voters to draw on, Trump’s hopes for victory ride almost exclusively on those elusive Reagan Democrats. In reality, however, Reagan Democrats have become the Republican version of the Loch Ness monster — everyone claims to have seen them, but they may not really exist.