Even though former Secretary of State Hillary Clinton won all five primaries last week, top campaign officials for Democratic presidential candidate Bernie Sanders insist that the Vermont senator still has a reasonable chance to win the nomination.
In many respects, the Sanders campaign looks at their race within the framework of a sporting event.
They say they started as serious underdogs when Sanders announced last May. They point out that he's now won several states and has more individual campaign contributions than anyone who has ever run for president.
Tad Devine is the chief strategist for the Sanders campaign. He says the path to the nomination is revived with victories Tuesday night in Utah and Idaho, and a strong showing in Arizona.
"We're at half-time here and we agree that we're behind but we also think we're going to win this game and we're going to finish ahead and we see a path to get there," says Devine. "And we believe the back end of the process is as favorable to Bernie as the front end of the process was for Hillary."
Some Democrats are calling on Sanders to tone down his strong criticism of former Secretary of State Hillary Clinton. But Sanders campaign manager Jeff Weaver says that's not going to happen.
"I anticipate the tone will remain the same," says Weaver. "I think there are important differences between Secretary Clinton and Bernie Sanders in terms of their record, in terms of their agenda."
Former Middlebury College political science professor Eric Davis says Sanders faces a tough, uphill fight to win the nomination.
Because the Democrats award delegates based on the percentage of the vote that each candidate receives in an individual state, Davis says Sanders has to win many upcoming states by a big margin.
"But if he doesn't get that 58 to 60 percent week after week that percentage keeps creeping up each week you get closer to the end of the primary and caucus season," said Davis.
Some of Clinton's supporters are suggesting that the time has come for Sanders to drop out of the race. Davis disagrees.
"I think these people who are saying that he should suspend his campaign and wrap things up really aren't focusing on almost the moral obligation that he has to his supporters who have been so strong supporting him all these months, and continue as an active candidate until the end," said Davis.
Sanders fundraising efforts remain very robust. In February, he raised just over $43 million compared to $30 million for Clinton. It marks the second month in a row that Sanders has raised the most money in the Democratic race.