The process -- which the party believes will take two days -- comes after the state's treasured first-in-the-nation contest fell into turmoil as the reporting methods for the more than 1,700 precincts broke down, halting the emergence of a clear winner and forcing a slow rollout of partial results.

It took the party days to release the full count of votes and multiple campaigns highlighted errors in those counts after they were released.

Sanders' campaign asked for a recanvass of 25 precincts and three satellite caucuses in the state, arguing that if "errors" are corrected, the Vermont senator would pick up one national delegate. Buttigieg's campaign, meanwhile, asked for a recanvass of 66 precincts and all satellite caucuses in the state, a total of 143 precincts, the Iowa Democratic Party said.

Initially, it appeared no campaigns were eager for a recanvass. But Sanders' campaign always reserved the right to call for a partial one.

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