Bernie Sanders significantly outraised his Democratic presidential rivals in the final three months of 2019. He is very much in the hunt for the first three contests of the primary season. He has run second, behind Joe Biden, in national polls for most of the past year and matches up better head-to-head against President Trump than either Elizabeth Warren or Pete Buttigieg. When Sanders supporters complain that the political press isn’t giving their guy the attention he deserves, they have a point.

Odds are that the Vermont senator won’t be the next president, but it isn’t out of the question. The RealClearPolitics polling average has him leading in Iowa and New Hampshire and less than a point out of second place in Nevada, the third contest. If he were to win a couple of these early races, he could lose the fourth in South Carolina, where he trails badly, and still have some momentum going into Super Tuesday on March 3.

Mr. Sanders’s $34.5 million fundraising haul in the fourth quarter was so impressive because the Democratic field remains so crowded. Mr. Trump raised $46 million for his campaign over the same period, but Republican donors don’t have 14 candidates to choose from. Moreover, the average donation to Mr. Sanders’s campaign was less than $20, and many of his donors are repeat low-dollar contributors. That suggests an intensity among his core supporters that can help him in caucus states, like Iowa and Nevada, which tend to reward the candidates who have the most engaged and motivated voters.

Four years ago, Mr. Sanders virtually tied Hillary Clinton in the Iowa caucuses and easily won the New Hampshire primary. On Super Tuesday in 2016, he picked up four more states—Colorado, Minnesota, Oklahoma and Vermont—and lost Massachusetts by a whisker. This year, Michael Bloomberg will be on the Super Tuesday ballots, and whatever votes he garners likely will come at the expense of fellow moderate Joe Biden, which could help Mr. Sanders.

If his campaign starts strong, it’s possible that the Democratic establishment could turn on Bernie like it did four years ago. But that runs the risk of alienating his large and enthusiastic base of supporters, and it’s hard to see Democrats beating Mr. Trump without the Sandernistas chipping in. The rule requiring a candidate to get at least 15% of the vote in a state to be awarded any delegates should also work in the senator’s favor. As the number of candidates dwindles to three or four, his grass-roots support and sizable war chest should allow him to meet the threshold and again go the distance. After Super Tuesday in 2016, he won in more than a dozen additional states, including the general-election battlegrounds Wisconsin and Michigan, which Mrs. Clinton lost.


Mr. Sanders’s biggest weakness remains his lack of support among older blacks, who are most likely to cast a ballot in the primaries. Yet these voters continue to tell pollsters that their chief concern is electability, and a few early wins by Mr. Sanders might go a long way toward convincing them that he can prevail in November.

Right now, black voters are solidly behind Mr. Biden, not only because he was Barack Obama’s vice president but also because they believe he can beat Mr. Trump. Should Mr. Biden stumble, it’s anyone’s guess where they might turn. James Clyburn, a black congressman from South Carolina, told CNN in November that blacks are ambivalent about Mr. Buttigieg because he is openly gay and many older blacks still hold socially conservative views about homosexuality. “I know a lot of people my age who feel that way,” said the 79-year-old Democrat. “I’m not going to sit here and tell you otherwise. I think everybody knows that’s an issue.”

When it comes to Ms. Warren, the issue for black voters may boil down to her character, and here Mr. Sanders has the advantage of sincerity and consistency. By contrast, Ms. Warren raised millions from wealthy people to run for office and now denounces others who do the same. She sent one of her two children to a private school but wants to limit the choices for low-income families who lack her resources. She spent her adulthood posing as a Native American to advance her career by taking advantage of policies designed to help racial minorities. Mr. Trump thinks this is a laugh line, but black voters might not find it so funny.

Mr. Sanders’s socialism is the last thing America needs, and let’s hope Democrats reject it. But in a country this divided, and with voters on both sides this motivated, the plain truth is that the president is vulnerable to anyone his opponents nominate. Which is all the more reason for journalists to stop treating the Sanders candidacy as a sideshow.