Fri, Nov 9, 2012 2:45 PM EST

The nation was able to choose a new president without incident on Tuesday night. But three days after the presidential election, the state of Arizona is not only not done tallying up votes--it's now actually tallying up the number of uncounted votes. And the number is getting larger by the day. Today Arizona advocacy groups are demanding the Department of Justice get involved to figure out what exactly is going on and protect the integrity of the state elections. Some 631,000 ballots cast in Arizona have yet to be counted, Arizona Secretary of State Ken Bennett said [in a statement]( Thursday. The number was 602,334 on Wednesday. Hanging in the balance are several hotly contested races, including Maricopa County Sheriff Joe Arpaio's effort to hold onto his seat for a sixth term. In Maricopa County alone 459,000 uncounted early and provisional ballots surely could swing the race either way--as of Tuesday night Arpaio held a 90,000-vote lead over Democratic challenger Paul Penzone. "We're deeply concerned by these shocking allegations and the notion that days after the election, nearly half a million Arizona ballots haven't been tallied," Monica Sandschafer, executive director of the Arizona Center for Empowerment said in a statement. "If true, this means that the voices of 1 in 15 Arizonans are simply being discarded. Nearly half of all early ballots in Maricopa County have yet to be counted."