With the North Carolina U.S. Senate race in a dead heta, state election officials say they have discovered 145 names on the voting rolls who are ineligible to vote because they are illegal immigrants who have been granted President Obama’s Deferred Action for Childhood Arrivals status.

According to a Winston-Salem Journal report, the State Board of Elections discovered the potential illegal voters Tuesday night when the N.C. Division of Motor Vehicles ran a search for DACA licenses. The 145 DACA recipients whose names appear on the SBOE’s voting rolls will be sent letters requesting documentation that they are citizens, the report noted.

DACA beneficiaries in North Carolina are able to obtain drivers licenses, but they are not able to vote.

The Journal notes that it is likely more ineligible people may still remain on the voting rolls.

Nearly 10,000 names on the rolls are tagged by the DMV as “legally present,” according to elections and transportation officials. But that doesn’t mean that all 10,000 are ineligible to vote at this time. These are license holders who were not U.S. citizens when they got a license. They may have been green-card holders, foreign workers or foreign students, for example. Most have become U.S. citizens since getting a license, according to an estimate by elections officials based on a sample of the overall list.

According to the report, earlier this month the SBOE officials did a sample cross-check of 1,600 of the 10,000 “legally present” names against a Department of Homeland Security database and found that 94 percent were U.S. citizens and eligible to vote. However, that still meant that six percent were ineligible, meaning if the ratio held for the whole 10,000, 600 people would be ineligible.

Mike Charbonneau, a DMV spokesman, told the Journal that it is now cross checking all the names.

While the officials work to cross check names, early voting is set to start in the state Thursday.

“We want to know how such a large number of non-U.S. citizens were ever registered to vote in the first place,” Jay DeLancy, executive director of the Voter Integrity Project of North Carolina, told Watchdog.org. “There is clearly a system failure here and we need the Board of Elections and the DMV to help the Legislature and the public understand where the problem lies.”