As Iowa Democrats streamed into their local caucuses Monday evening, they told pollsters by a margin of 61% to 37% that they would rather see the Democratic Party nominate a presidential candidate who can “beat Donald Trump” than one who “agrees with you on major issues.” But according to partial returns released Tuesday afternoon, their votes have made Sen. Bernie Sanders once again a leading candidate for the Democratic nomination.

It is difficult to believe that Mr. Sanders’s supporters consciously placed ideological commitment above victory in November. They must believe, as Mr. Sanders does, that his nomination will catalyze a “political revolution” in which millions of previously uninvolved voters will surge into the electorate and replicate the Democratic sweep of 1932.

Such expectations have a long history. Barry Goldwater’s supporters embraced them in 1964, as did George McGovern’s in 1972. Neither candidate fared well. The recent NBC News/Wall Street Journal survey is the latest to offer evidence that this time would be no different.

Let’s start with ideology. Fifty-two percent of registered voters expressed positive views about capitalism, compared with 18% voicing negative views. Regarding socialism, only 19% were positive while 53% were negative, including 41% who were “very negative.” These numbers haven’t budged over the past 15 months. The Republican attack on socialism, a steady drumbeat since last year’s State of the Union address, would throw Sen. Sanders on the defensive.

The Vermont senator’s ideologically aware defenders will retort that he is not the scary kind of socialist who wants government to take over the means of production. Rather, they cast him as a warm and fuzzy social democrat who wants to use government to reduce insecurity and bolster opportunity for all. But Mr. Sanders has proposed not only the complete nationalization of the U.S. health-care system but also a $2 trillion federal takeover of electrical power production. Public support for Medicare for All plummets when people are told that it would eliminate private health insurance, a core feature of Mr. Sanders’s plan.


Because there are more conservatives than liberals in the electorate, Democratic presidential nominees cannot triumph unless they win a strong majority of moderate voters. But only 11% of these voters have a positive view of socialism, compared with 53% who oppose it.

Unless a Sanders candidacy could somehow reconfigure the political map, he would need to retake at least Pennsylvania and Michigan to have a serious shot at 270 electoral college votes. But the less-educated white voters who dominate these states’ electorates are hostile to socialism, even more so than whites with college degrees. Only 12% of white voters without college degrees are favorable toward socialism, while 63% disfavor it—and 54% view socialism in a very negative light. Whatever the case in Vermont, socialism is not a winner in the Midwest.

Mr. Sanders claims his uncompromising message gives him a unique opportunity to translate popular passion into votes. If so, the NBC/WSJ poll results don’t show it. Only 13% of voters report being “enthusiastic” about his candidacy, compared with 43% who are “very uncomfortable.” (The comparable numbers for Joe Biden are 14% and 35%.) Among swing voters, 31% are very uncomfortable with Mr. Sanders, compared with only 19% feeling the same about Mr. Biden.

These findings help explain why Mr. Biden beats President Trump by a margin of 31 points—50% to 19%—among these swing voters, while Mr. Sanders prevails by only 18 points—42% to 24%. In a close election, Mr. Biden’s greater appeal to this group could mean the difference between victory and defeat. In addition, Mr. Biden outperforms Sen. Sanders against Mr. Trump in nearly all swing states, including Pennsylvania, Wisconsin, Minnesota, North Carolina, Florida, Arizona, and even New Hampshire.


To be sure, in eight surveys conducted since the beginning of 2020, Sen. Sanders averages 49% against Mr. Trump’s 46%. But Mr. Biden does better, beating the president by an average of 50% to 45%. If Mr. Sanders became the Democratic nominee, moreover, Republicans who have held their fire up to now would unleash volleys of opposition research at him, and the results would not be pretty.

Mr. Sanders came unexpectedly close to winning the Democratic nomination in 2016. With his strong showing in Iowa, he may be poised to improve on that performance. He is the odds-on favorite to prevail in New Hampshire next Tuesday, and his cultivation of Hispanic voters could propel him to victory in Nevada. If so, he would crash into Joe Biden’s South Carolina firewall with enormous momentum. Irresistible force might prevail over the immovable object. And Super Tuesday is only three days after the South Carolina primary.

All the major contenders in Iowa say they are continuing to New Hampshire. But if they remain in the race too long, they may enable Mr. Sanders to win the nomination with only a modest plurality of the primary electorate. Before the end of February, the leading representatives of the center-left must coalesce around the candidate who has best demonstrated the ability to unite the anti-Sanders vote and lead the party to victory in November. The alternative could be an epic disaster for Democrats and the country.