The head of the Iowa Democratic Party apologized somberly Tuesday for botching the highly anticipated release of the party's caucus results, calling the delay unacceptable.

"I apologize deeply for this," said party chair Troy Price, shortly before releasing the first batch of precinct results.

Campaigns, party volunteers and regular Iowans expressed confusion and frustration at the lack of clarity on what is often one of the most closely-watched nights in American presidential politics.

The results, once released, reflected 62% of Iowa's precincts from all 99 counties. It showed former South Bend, Indiana, Mayor Pete Buttigieg leading the field, with 26.9% of state delegate equivalents. U.S. Sen. Bernie Sanders of Vermont followed, with 25.1%. U.S. Sen. Elizabeth Warren of Massachusetts was in third, at 18.3%. At 15.6%, former Vice President Joe Biden and U.S. Sen. Amy Klobuchar of Minnesota (12.6%) rounded out the top five.

Live results updates:

The party, under pressure to modernize the caucuses and make them more transparent, added a new app for reporting results, new ways of reporting results and new back-up systems. Those systems failed Monday. Price blamed a "coding error" for the app failing Monday night.

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In a hastily organized news conference in downtown Des Moines on Tuesday afternoon, Price said the party faced "multiple reporting challenges" Monday. He said out of an abundance of caution, he delayed releasing results to review the incoming data.

Price said a "thorough, transparent and independent examination" of what happened on caucus night would take place.

"Let me be clear: My number one priority has been on ensuring the accuracy and integrity of the results," Price said as reporters crowded around the staging where he spoke. "And we have been working all night to be in the best position to report results."

Price also insisted the raw data was secure. He said the party has a paper trail and other documentation to help verify results.

"The bottom line is that we hit a stumbling block on the back end of the reporting of the data," he said. "But the one thing I want you to know: We know this data is accurate."

Price appeared remorseful during the news conference. The delayed results have heightened the national debate over whether Iowa should continue to hold its coveted top spot on the nominating calendar.

"This is personal to me," he said. "I'm a lifelong Iowan. I have caucused for 20 years. And I know how important it is ... to our party, to our state, and to everyone, from our neighbors to new voters, to be able to come together all across this state. We want Iowans to be confident in the results and in the process, and we are going to take the time that we need to make sure that we do just that."

Among the questions reporters asked was whether Price felt pressure to step down as chair.

"When I ran for chair, I made a commitment to see the caucus process through," he said. "That is what I am working on, that is what I will continue to work on, and whatever happens after that ... is to be determined."

Barbara Rodriguez covers health care and politics for the Register. She can be reached by email at bcrodriguez@registermedia.com or by phone at 515-284-8011. Follow her on Twitter @bcrodriguez.

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