MANCHESTER, N.H. — Three days after the Iowa Democratic caucuses, Vermont Sen. Bernie Sanders claimed a "decisive victory" Thursday, pointing to his 6,000-vote lead in raw popular votes in the first alignment and downplaying partial results that show a tiny lead for former Mayor Pete Buttigieg in state equivalent delegates.

"We are holding a press conference that should have occurred three nights ago in Des Moines, but for the inability of the Iowa Democratic Party to count votes in a timely fashion," Sanders told reporters packed inside his New Hampshire campaign headquarters.

"That screw-up has been extremely unfair to the people of Iowa, it has been unfair to all of the candidates and all of their supporters. So what I want to do, three days late, is thank the people of Iowa for the very strong victory they gave us Monday night."

Sanders' pronouncement comes as Iowa results are still not fully counted following the malfunction of a cell phone app used to report results. A backup phone line for results was also clogged as precinct chairs tried to call in results. Buttigieg, former mayor of South Bend, Indiana, was the first to claim victory on caucus night due to his lead in state delegate equivalents, which are tied to the number of delegates to the state convention each candidate earned on caucus night.

But Sanders has slowly closed the gap in Buttigieg's lead in SDEs and has maintained a lead in the popular vote tallies since results began trickling out Tuesday.

More:What really went wrong on Iowa caucus night? Inside the problems that led to results being delayed

The Vermont senator's declaration also came just minutes after National Democratic Party Chair Tom Perez called for a "re-canvass" of the Iowa caucus results.

"We won an 8-person election by some 6,000 votes. That is not going to be changed," Sanders said in response to the party chair's push for a recanvass. "What may be changed in this so-called recount is a few SDEs."

Sanders bemoaned what he called an "enormously complicated" caucus system. He said the true measuring stick for victory is that, out of 180,000 total Iowa voters, "some 6,000 more Iowans came out on caucus night to support our candidacy than the candidacy of anyone else."

"And when 6,000 more people come out for you in an election then your nearest opponent, then we here in northern New England call that a victory."

More:A New Hampshire primary win is key for multiple Democrats. Here's what we know

That 6,000 number refers to the lead Sanders had in the first preference alignment Monday night. He also holds a lead of thousands in the final alignment totals. Sanders called state delegate equivalents the preference of "cable news and political pundits," but said they have "greatly diminished significance" than previous elections because of party rule changes.

He said "mathematical problems" identified by the Sanders campaign could mean he actually ends up topping Buttigeig in SDEs, but that tally is "meaningless" because he and Buttigieg will ultimately end up tied in the number of national delegates, which determine the eventual nominee.

"At the end of the day, what I expect, what will almost definitely happen is Mr. Buttigieg and I will end up with the same number of delegates ... Ain't gonna change. And what will certainly not change is that in terms of the popular vote, we won a decisive victory," Sanders said.

Buttigieg has enjoyed an 8-percentage point bounce in New Hampshire following his performance in Iowa, according to a Suffolk University poll that showed him with support from 19 percent of likely New Hampshire primary voters. But he still trails Sanders' 25 percent.

A Monmouth University poll released Wednesday showed Sanders surging since last month, gaining 6 percentage points and leading all of his competitors.

Reach Joey Garrison and on Twitter @joeygarrison.