Bernie Sanders, his momentum slowed by a loss to Hillary Clinton in Nevada, faces two tests in the weeks ahead: parceling out his formidable resources to the states that offer his best targets, and boosting turnout in what has been a mediocre year for it.His path to the Democratic nomination, already steep, has narrowed considerably now that Clinton has re-established herself as the all-but-prohibitive front-runner. To win the nomination, Sanders acknowledged Sunday that he will have to begin winning again, as he did when he trounced Clinton in New Hampshire.

“We’re studying that issue very closely, obviously, as to where we allocate our resources and allocate my time,” Sanders said.

Although Sanders campaigned in South Carolina on Sunday, his prospects there are dim — as evidenced by the fact that he neglected to mention the Palmetto State’s contest as he ticked off a handful of upcoming states where he can win.

Nonetheless, the race will probably continue for a long time, as it did in 2008 — with one factor reversed. This time, the African American vote is expected to be a big advantage for Clinton.

Sanders confident heading into Super Tuesday

Democratic presidential candidate Bernie Sanders said he is confident of continuing his campaign into Super Tuesday in March, when most of the states elect their party nominee for the White House. (Reuters)

Clinton is a heavy favorite in South Carolina, the state where her defeat by Barack Obama marked a turning point in the Democratic primary eight years ago. Her support among African Americans, who make up more than half of the Democratic electorate there, gives her what appears in polls to be an insurmountable advantage.

Then the campaign moves into a trove of diverse, delegate-rich Southern states that are also considered favorable terrain for Clinton.

Sanders has the ability to remain in the race for the distance, thanks to his fundraising abilities — and to the Democrats’ system of allocating delegates proportionally rather than in a winner-take-all fashion.

In Nevada, for instance, Sanders lost to the former secretary of state by more than five percentage points but still came away with almost as many delegates as she did, taking 15 to her 19.

“We are in this race to the convention,” Sanders said Sunday on NBC’s “Meet the Press.” “I think we’ve got some states coming down the pike that we’re going to do very, very well in. I think, you know, if you look at national polling, our support is growing.”

He listed five Super Tuesday states in which he said he has “a good shot” March 1: Colorado, Minnesota, Massachusetts, Oklahoma and his home state of Vermont.

Former Secretary of State Hillary Clinton, a Democratic presidential candidate, gives a victory speech after winning the Democratic Nevada Caucus on Saturday. (Melina Mara/The Washington Post)

Colorado and Minnesota both choose their delegates in caucuses. The caucus system, which generally brings out only the most motivated activists, presumably makes them friendlier to a candidate such as Sanders, who has inspired a movement of liberal Democrats. But caucuses require a bigger investment of time, making it harder to draw out less committed voters, which could give Sanders a disadvantage. One line of thinking within the campaign, for instance, is that he would have won Nevada had it been a primary instead of a caucus. And turnout was not down in New Hampshire, the only Democratic primary to be held so far.

In 2008, Obama caught Clinton’s presidential campaign off balance by running up its delegate totals in caucus states — a mistake that Clinton’s team has vowed it will not repeat. She has won the first two caucus states, Iowa and Nevada. And her Colorado and Minnesota operations have been up and running since last fall.

Sanders strategist Tad Devine, however, noted that his candidate received more votes than any of either party in the history of the New Hampshire primary — which he said proved that the senator could do well in an electoral setting like that state, where independents are allowed to cast ballots in the Democratic primary.

New England is friendly turf for Sanders, given its liberal leanings.

But ruby-red Oklahoma might seem a counterintuitive choice for Sanders. His campaign often notes that the state has become so heavily Republican that anyone who remains a Democrat is probably pretty liberal.

Devine said that Sanders will probably mount a strong primary challenge to Clinton in Kansas and Nebraska, both of them likely to go into the Republican column in November.

More recently, Sanders and his strategists have begun talking up their chances in Michigan, which holds its primary March 8. Both the Sanders and Clinton campaigns last week began airing their first television ads.

“We can have a big showdown in Michigan,” Devine said. “If we can beat her in Michigan, I think we can go into March 15 with a lot of momentum.” On that date, five states vote.

One area where Sanders acknowledged he must do better is in voter turnout. The constituencies where he does best — especially young people — are notoriously difficult to draw to the polls.

And in the caucuses so far, overall numbers of Democratic voters showing up have been nowhere near the levels they were in 2008, the last time there was a contested nomination.

“What I’ve said over and over again, we will do well when young people, when working-class people come out,” Sanders said in his NBC interview. “We do not do well when the voter turnout is not large. We did not do as good a job as I had wanted to bring out a large turnout.”

Another built-in advantage for Clinton as the establishment favorite are “superdelegates” — people who are given votes at the convention by virtue of their elected offices or positions in the party. There are more than 700 of them, and they account for nearly one-third of the number it takes to get the nomination.

The Clinton campaign has declined to say how many superdelegates it counts in its column. But the Associated Press reported last week that Clinton leads Sanders in superdelegates, 449 to 19.

“We’re sort of up against everybody,” Devine acknowledged, but he added that it is a problem that can be cured only by beating Clinton in the primaries.

“Until we prove he’s the strongest candidate, that’s not an argument we’re going to win,” Devine said.

Karen Tumulty is a national political correspondent for The Washington Post, where she received the 2013 Toner Prize for Excellence in Political Reporting.