This article was updated at 12:43 pm EST to include a statement by Zac Moffatt of the Romney campaign.

Republican presidential candidate Mitt Romney may have lost track of thousands of key voters in swing states, according to former campaign aides, who say a faulty app meant to track voters failed on Election Day.

According to the Romney campaign, a faulty app nicknamed Orca shutdown midway through Election Day, leaving volunteers on the ground in swing states, such as Florida, without any means to identifying Romney supporters.

“Our dashboard was down from when the election started, when the polls opened and people first tried to log in — by people, I don’t mean people at the precincts, I mean people in the campaign headquarters and in the war room, we could never log onto the system and get voter data ever,” said one campaign official, according to the National Review.

Sources within the Romney campaign say the software contained erroneous advice for poll-watchers, and it even crashed on election night. Meanwhile, the Obama campaign rode its own version of the app, “Narwahl,” to victory.

While various sources within the Romney campaign have confirmed that the app went down for several hours on Election Day — possibly costing Mr. Romney thousands of votes — a handful of former Romney campaign officials denied reports the app failed.

“That’s absolutely not true,” said one Romney aide. “We have tons of data showing volunteers actively marking voters as having ‘voted’ in all states – including the Midwest.”

According to The Verge, some Romney officials say the app was hacked during Election Day, causing it to eventually crash. In a piece published Thursday, The Verge notes that Romney campaign officials offered little or no evidence to support the claim that the app was hacked, adding that recent evidence points to an ill-designed app.

“By all accounts, Orca finally crashed hard the afternoon of November 6th, though there’s little to support the allegation that it was hacked,” according to The Verge. “PIN and password problems could have been the result of either technical issues or user error, and given how confusing the system seems to have been for volunteers and organizers alike, it’s hard to tell which is more likely.”

More likely than not an overwhelming amount of data pushed the system to its brink. Speaking Thursday, Romney campaign digital director Zac Moffatt said the campaign failed to anticipate the amount of information that would flow into the data center, forcing campaign officials to work on the spot to adjust settings and get the program up and running.

“The primary issue was we beta-tested in a different environment than [headquarters Boston Garden],” he said. “There was so much data coming in — 1200 records or more per minute — it shut down the system for a time. Users were frustrated by lag, and some people dropped off and we experienced attrition as a result,” said Moffat. “The information came in, so you can’t say it didn’t work. You run into issues because it’s so massive in scale.”

Whether the app shutdown cost the Romney campaign any votes is up for debate. Romney officials say the failure likely cost Mr. Romney a few thousand votes, but it had a much larger impact on the field team, making them less effective during peak voting hours. A shutdown during peak voting hours likely left the Romney campaign with little to no information in regards to which voters had yet to cast a ballot.

Still, a major shutdown likely did not cost Mr. Romney the election. Scott Goodstein, the external online director for the Obama campaign in 2008 and the founder of Revolution Messaging told The Huffington Post that if a candidate hasn’t reached voters by Election Day, it’s probably too late.

“In a national campaign, what additional things are the headquarters really going to do to move resources? Will an additional auto-call last minute really make a difference in a market like Northeast Ohio, which has been saturated for three months full of auto-calls?”