A top Democratic official said Thursday he had warned Iowa Democrats last month against using an untested app to transmit returns in the Iowa caucuses, whose results were thrown into further disarray as the party’s national leader called for a recanvass.

Jim Roosevelt, co-chairman of the Democratic National Committee’s powerful Rules and Bylaws Committee, said he and a colleague raised concerns over the phone with Troy Price, the chairman of the Iowa Democratic Party, and that Price assured them the app had been properly vetted.

“We said, ‘At scale?’ ” Roosevelt recounted of the January conversation. “He said yes. But it turns out it’s not the case.”

That warning, which has not been previously reported, raises new questions about the decision-making of the Iowa Democratic Party in planning for its high-stakes caucuses, which have been engulfed in uncertainty since the app broke down on caucus night. A spokeswoman for Price said the state party chairman did not remember such a call.

Democrats had hoped Thursday to finalize the Iowa results so they could move ahead with choosing a nominee to take on President Trump. Instead, the chaos continued as a breach opened between national and state Democrats, inaccuracies continued to emerge and two candidates seized on the results to claim victory.

Sen. Bernie Sanders (I-Vt.) argued — at a time Thursday afternoon when 97 percent of precincts had been counted — that it was clear he got more votes than anyone else.

“When 6,000 more people come out for you in an election than your nearest opponent, we here in northern New England call that a victory,” Sanders said while campaigning in New Hampshire. When Iowa Democratic officials on Thursday night released 100 percent of the precincts, his campaign said the update “confirms” his victory.

Former South Bend, Ind., mayor Pete Buttigieg, had proclaimed victory Monday night with no official results reported. During an appearance on ABC’s “The View” Thursday morning, he characterized the race as “neck-and-neck.” But on Thursday night, his campaign also claimed he had won.

Tom Perez, chairman of the Democratic National Committee, signaled he was losing patience with the confusion and the Iowa party’s handling of it.

“Enough is enough,” Perez tweeted. “In light of the problems that have emerged in the implementation of the delegate selection plan and in order to assure public confidence in the results, I am calling on the Iowa Democratic Party to immediately begin a recanvass.”

The state party gave no indication it planned to honor Perez’s demand, instead issuing a statement noting that it is the campaigns that are entitled to request a recanvass. None has so far made such a request, and Sanders and Buttigieg indicated Thursday they would not.

A recanvass would mean a hand audit of the math worksheets and reporting forms that are completed on caucus night at each of the more than 1,750 precincts across the state. It would differ from a full recount, which involves a hand count of each of the “presidential preference cards” completed by caucus-goers.

The state party, in new measures for 2020, introduced an opportunity for campaigns to request a recanvass, or a recount if necessary, if they could show that new figures could alter the allocation of delegates to the Democratic National Convention.

Any campaign requesting a recanvass would have to pay for it. Party rules do not specify what happens if a third party, such as Perez, intervenes.

Perez’s comment arose from widespread concerns about lingering uncertainties in Iowa, including on whether new figures from the state’s “satellite” caucuses square with guidelines for allocating delegates, according to a Democratic official who was not authorized to speak publicly.

More than 1,500 caucus-goers participated at these alternative locations, which are designed for Spanish speakers, night workers and others who have trouble attending a traditional caucus. The satellite caucuses were introduced for the first time this year.

It’s not the first time tensions have erupted between national and Iowa Democrats over competing pressure for access, security and efficiency in the caucuses. Last year, the DNC effectively rejected a plan for “virtual caucuses,” because of fears that the mobile software could not be secured against hacking.

Democrats had hoped Monday’s caucuses would mark the triumphant launch of their effort to oust a president they despise and provide clarity to an unwieldy field.

Instead, three days later the party found itself with two candidates, Sanders and Buttigieg, with bragging rights. Sanders led in the popular vote by 2,631 votes on Thursday night, but Buttigieg had a narrow lead in the percentage of delegates won, at 26.2 percent to Sanders’s 26.1 percent.

At a news conference in Manchester, N.H., Sanders said Buttigieg’s edge in state delegates was “meaningless.” More important, he said, were delegates to the national convention, where the two would derive equivalent backing from Iowa.

But the key outcome, he said, was that more Iowans had chosen him than any of the other candidates.

“What I want to do today, three days late, is to thank the people of Iowa for the very strong victory they gave us at the Iowa caucuses on Monday night,” Sanders said.

Buttigieg, at a stop in Merrimack, N.H., said his campaign had been “absolutely electrified … by the extraordinary validation of this campaign’s vision that we had in Iowa on Monday.”

Still, he added, “I’m also mindful and humbled by the fact that New Hampshire is New Hampshire. And New Hampshire is not the kind of place to let Iowa or anybody else tell you what to do.”

Sen. Elizabeth Warren (D-Mass.) and former vice president Joe Biden have lagged behind Sanders and Buttigieg as the Iowa results have unfolded, putting pressure on their campaigns to bolster their showing in New Hampshire.

At least one contender was willing to accept Sanders’s claim. “It sure looks like Bernie won Iowa,” business executive Andrew Yang tweeted. “Excited to compete for the win in New Hampshire on Tuesday!”

So even while the Iowa chaos continued, the presidential hopefuls forged ahead in that state with an eye toward Tuesday’s primary. A new Monmouth University poll showed Sanders and Buttigieg on strong footing in New Hampshire, at 24 percent and 20 percent, respectively, in a survey with a margin of error of four percentage points. Biden, who described his fourth-place finish in Iowa as a “gut punch,” registered at 17 percent, and Warren was at 13 percent.

New Hampshire gained in salience as the closely watched contest in Iowa remained muddled. The caucuses were thrown into confusion Monday night as candidates and caucus-goers waited for results that never came, and it soon emerged that the mobile app hastily built to transmit precinct returns to the state party had failed.

A backup hotline for calling in the results then became overloaded — at least partly because of prank calls placed by Trump supporters, according to Mandy McClure, a spokeswoman for the Iowa Democratic Party. Quickly, the caucuses held out by Iowa Democrats as a model of participatory democracy became a lesson in the perils of conducting elections in the digital age.

The Iowa Democratic Party had initially solicited bids jointly for the mobile app and for its “virtual caucuses,” which would have allowed Iowans to participate by phone and was later canceled.

The party initially hoped to identify a vendor for both as early as May 2019, according to an individual familiar with the request.

When plans for the virtual caucuses were scrapped in September, the state party pressed ahead with its aim to build a mobile app for transmitting results, as it had done in 2016. But it was only at the last minute that it was able to complete a contract with a Democratic-aligned start-up, Shadow Inc., to build the app, handing over about $63,000 in two installments in November and December.

But secrecy surrounded the process. The state party kept the name of the developer private and delayed the app’s rollout to guard against hacking, according to an official with the Iowa Democrats who spoke on the condition of anonymity to discuss sensitive matters. And Roosevelt, the DNC’s Rules and Bylaws co-chairman, said state party leaders would not reveal who had vetted the software.

Roosevelt said that when he raised concerns with Bob Lord, the DNC’s chief security officer, Lord told him the app was not a severe cybersecurity risk because it would be used only for transmitting results, not voting. The national party saw the functionality of the reporting app as the responsibility of the state party and its vendor, according to a Democratic official familiar with the matter.

The Iowa Democratic Party now plans to bring in a third-party group to examine what went wrong with the technology, said Jean Pardee, a member of the party’s state central committee, whose members participated in a conference call Wednesday.

Iowa Democrats reiterated that however problematic the delays, the reliability of the results is beyond dispute. “Maybe efficiency and timeliness are fair critiques, but the integrity of this caucus has never been in question,” said Jim Mowrer, former vice-chairman of the Iowa Democratic Party.

But Sanders joined the growing list of prominent Democrats sharply criticizing the Iowa party’s performance.

“That screw-up has been extremely unfair to the people of Iowa,” Sanders said. “It has been unfair to the candidates — all of the candidates — and all of their supporters.”

Michael Scherer, Amy B Wang and Cleve Wootson Jr. contributed to this report.