PHOENIX (Legal Newsline) - Arizona Schools Superintendent Tom Horne declared victory on Sunday in the GOP primary for state attorney general.

His opponent for the nomination, former Maricopa County attorney Andrew Thomas, has said he won't concede until all of the ballots are counted. That likely won't be until Tuesday, state officials said.

Horne, in a follow-up statement released Monday, confirmed he was the Republican nominee. Provisional ballots in Pima and Miracopa counties were complete, he said, and his lead has expanded to 853 votes statewide.

Horne, in his original statement, said he was looking forward to the November election.

"I am confident my message about securing the border, strengthening consumer protection, and creating a positive legal climate for jobs will resonate once again," he said.

The Republican primary for the state's attorney general post -- held last Tuesday -- has been a tight one.

As of late Thursday, Horne led Thomas by fewer than 500 votes. A spokesman for the secretary of state's office said there were still an estimated 34,000 early ballots that hadn't been yet counted as of Friday.

On top of that, the office said there were another 20,000 "provisional" ballots cast by people who registration was questioned, most likely because voters showed up at the poll without proper identification. Those ballots will not be counted unless those voters showed up with the necessary documents on Friday, the office said.

Horne looks to face Felecia Rotellini, the former state financial regulator and Democratic nominee for attorney general, in November.

State Rep. David Lujan, Rotellini's opponent in last week's primary, conceded late Thursday.

Terry Goddard, the current attorney general, is precluded from seeking a third term. He is running for governor against incumbent Jan Brewer.

From Legal Newsline: Reach Jessica Karmasek by e-mail at jessica@legalnewsline.com.