The Sanders team is trying to build momentum ahead of the Iowa Caucuses set for Monday, February 3. With a long-fought battle happening since early last year, the days are turning into hours before the first voters get a chance to begin the process of selecting a presidential nominee for the Democratic Party in 2020. Despite all the handwringing from establishment figures and party insiders, who continue to sound nervous of a Bernie win, it appears that Sanders is on the cusp of winning in Iowa, though the caucuses are historically unpredictable and last-minute decisions by voters could upend the race we think we’re watching.

Despite the unpredictable nature of Iowa, Sanders on the campaign trail is trying to motivate supporters and speak as if he is now the one to beat:

Ever the insurgent, Sanders is spending his final days on the trail in Iowa predicting a win here and beyond. He has boasted of his “excellent” chances in the first-in-the-nation caucuses on Monday and already predicted a win in delegate-rich California in March. The Vermont senator is openly delighting on the stump as he is increasingly being talked about as the candidate to beat, at least for now.

“You can tell how good I feel by how nervous the establishment is getting,” Sanders told cheering supporters at a downtown auditorium in Sioux City, on Iowa’s border with Nebraska, on Sunday. “We’re their worst nightmare.”

Sanders’ confidence isn’t necessarily backed up by polling — which shows the same jumble of Democrats at the top in Iowa that have been there for months.

It’s true that some polls still show former vice president Joe Biden topping Sanders in Iowa by a few points, but the slight majority of polls in recent weeks have given Sanders a lead, and the momentum seems to be in his direction. The key for Sanders will be the turnout game and motivating his supporters to come out and vote because, unlike in 2016, it sure seems like Bernie has a serious chance at capturing at least two out of four early contests in February.

Whether he wins Iowa, or comes very, very close, he’s a much more sure bet in New Hampshire, where he won four years ago. If Sanders wins both states, it creates a rush to Nevada and South Carolina, where supporters of other candidates, like Elizabeth Warren, might decide to start peeling away and jump on board the train that could make it further out of the station this time.

What’s more, businessman Andrew Yang appears to have offered some tepid support or at least acknowledgment that some of his supporters in Iowa may end up switching to Sanders in later caucus rounds:

Andrew Yang said he won’t be surprised if his voters end up supporting Bernie Sanders in later rounds of the Iowa caucus voting — a development that could strengthen Sanders’s already-surging campaign in the state.

Speaking at a Bloomberg News reporter round table in Des Moines, Yang said there is an “overlap” between his supporters and those of the progressive Vermont senator.

“I think that Bernie and I do have a lot of overlap in support so it wouldn’t be surprising to me if many of our supporters head in that direction,” he said.

At Monday’s caucuses, Iowans will conduct a first round to pick their favorite candidate. Any candidate who falls short of the required support can direct his or her supporters to back a rival in a second round.

Yang holds a vocal and fervent fanbase and he does command around three to four percent support according to polling averages in Iowa. His numbers won’t go 100% to Sanders, but there is some overlap as Yang stated.

The question will be whether the dynamic changes if Sanders wins Iowa, then New Hampshire, and starts to look like a threat in Nevada and beyond, looking to Super Tuesday in states like California. Some Democratic Party insiders have threatened to become more involved in the race if it appears the party could belong to Bernie in 2020 as they fear his brand of democratic-socialism.

Momentum and excitement about a candidate aren’t often reflected in polling data and can’t accurately be quantified, so some analysts are still urging caution about overconfidence by any campaign, according to FiveThirtyEight:

In our Iowa forecast, Sanders still leads slightly (37 percent versus Biden’s 35 percent). This is unchanged from yesterday and is probably better thought of as a tie. Buttigieg and Warren’s chances haven’t really shifted in the last 24 hours.

Although Sen. Amy Klobuchar did tick up a little today thanks to some double-digit showings in today’s batch of polls, though she remains a decided underdog with only a 3 percent shot at winning Iowa. On balance, though, the newest Iowa surveys held some good news for Biden compared to some other recent surveys where Sanders did better, though the Vermont senator did still manage to make gains in two of today’s polls.

Based on the data alone, Sanders is ticking ahead by a few points. Based on enthusiasm on the ground, he would seem much further ahead than the numbers can reflect. All of this is to say that Iowa remains unpredictable, but it’s better to be in Bernie’s position than it is to be in Joe Biden’s, seemingly nipping from behind.