More than four hours after the caucuses started with Sen. Bernie Sanders , Sen. Elizabeth Warren , former South Bend, Indiana, Mayor Pete Buttigieg and former Vice President Joe Biden vying for first place, the first results of 1,600 precincts have yet to emerge.

And campaigns were told in the early morning hours Tuesday not expect any results until later in the day, two officials tell CNN.

"At this point now they need to get it right," one official said.

An Iowa Democratic official said results are still being collected -- and that will overnight if the precinct chairs keep calling them in. No time estimate was given to campaigns. "They literally have no verified results," a senior campaign adviser said. "We won't know anything until sometime Tuesday -- at least."

Amid anger, chaos and confusion, candidates took to the stage at their caucus headquarters one by one -- at a time when the victor would normally be expected to bask in the spoils -- to give versions of their stump speeches before heading on to the next contest, in New Hampshire next week.

The delay seems to have been caused by the state party's new system, which is counting the popular vote from a first round of voting, an updated tally once caucusgoers give their final verdicts and the figures for pledged delegates each candidate eventually wins.

"We found inconsistencies in the reporting of three sets of results. In addition to the tech systems being used to tabulate results, we are also using photos of results and a paper trail to validate that all results match and ensure that we have confidence and accuracy in the numbers we report," said Iowa Democratic Party Communications Director Mandy McClure in a statement. "This is simply a reporting issue, the app did not go down and this is not a hack or an intrusion. The underlying data and paper trail is sound and will simply take time to further report the results."

The logjam threatens to rob the eventual winner of the caucuses of some of the early bounce from their victory and is a poor look for a party trying to prove it is up to taking on Trump's fearsome political machine. It might offer candidates who do worse than expected some cover and is already raising questions about Iowa's place at the front of the presidential calendar.

The campaigns are livid.

The Biden campaign wrote a letter to the Iowa Democratic Party complaining about the "considerable flaws" in the vote reporting system.

Kate Bedingfield, an aide to the former vice president, cast doubt on the probity of the election.

"The integrity of the process is critical, and there were flaws in the reporting systems tonight that should raise serious concerns for voters," she said in a tweet.

Officials from two Democratic campaigns tell CNN they were told the app to tabulate results had crashed -- despite what the state party reported.

One candidate, Minnesota Sen. Amy Klobuchar , made a shrewd move to fill the political vacuum and gave a pseudo-victory speech -- grabbing the television spotlight in the absence of results giving other more favored candidates the win.

"We know there are delays, but we know one thing -- we are punching above our weight!" Klobuchar said.

Sanders predicted that he would have a great night -- even if it took time for the results to emerge.

"I have a good feeling, we are going to be doing very, very well in Iowa," he said. "The first state in the country has voted ... and today marks the beginning of the end for Donald Trump,"

"By all indications, we are going to on New Hampshire victorious," Buttigieg said at a wild rally in Des Moines. But the former South Bend mayor started his speech well after midnight on the East Coast and waited until most of his rivals had spoken -- likely depriving him of much of the political impact of his claim -- even if it turns out when results are eventually announced that he did win the caucuses.

Biden appeared happy to skip on to New Hampshire and later contests in which his campaign believes he will be more competitive than in Iowa.

"It looks like it's going to be a long night but I am feeling good," Biden said.

Earlier, CNN entrance polls showed that Sanders, Biden, Buttigieg and Warren were the early leaders among 11 candidates. Since voters can change their preferences inside the caucuses if their favorite candidates do not reach a minimum threshold, this data is preliminary and will likely change.

In the absence of official results, campaign managers were reading the tea leaves from information sent in by field staff to try to assess how they were performing. Two senior aides to the Buttigieg campaign, for instance, said that they were performing more strongly than expected, according to their internal tallies.

"Things look pretty good so far," one aide said.

Other campaigns were also contacting organizers in rural areas to try to get an early picture of how their candidates fared and how their efforts during months of campaigning are paying off.

A crucial first night gone sour

In a quirky exercise of in-person democracy, caucusgoers in more than 1,600 precincts are gathering in groups to show support for their favored candidates at the beginning of the caucuses, which could last a couple of hours.

Supporters of White House hopefuls who don't meet a threshold of 15% in any given precinct have the chance to recommit to "viable" candidates or go home -- and are facing a hard sell by pleading friends, neighbors and business contacts backing other candidates to join them before officials create final tallies.

Delegates are awarded proportionally and Iowa accounts for 41 of the 1,991 pledged delegates needed to capture the nomination at the Democratic National Convention in Milwaukee in July.

Republicans also hosted caucuses on Monday night in Iowa. There is little real competition -- CNN is projecting Trump will win the state.

The Iowa race took center stage after being largely overshadowed by the raucous Trump presidency, and the impeachment drama that is just wrapping up in Washington and kept the senators running for the Democratic nod off the trail at the climax of the Hawkeye State campaign.

It will test whether Trump's attacks on Biden have harmed perceptions of his electability among Democratic voters. The impeachment drama embroiled the former vice president since Trump leaned on Ukraine to dig up dirt on a rival who has long been seen as the national Democratic front-runner. The former Delaware senator has long styled himself, after a near half century in top level politics, as the best positioned Democrat to beat Trump -- and to restore what he says is the nation's fractured values and equilibrium.