Arizona's three competitive congressional races are still too close to call, including the Tucson-centered seat Rep. Ron Barber won in June to replace his former boss, Gabrielle Giffords.
Barber saw his small lead against Republican Martha McSally in the 2nd District disappear just before midnight, with McSally taking a tiny lead.
In the new Phoenix-area 9th District, Democrat Kyrsten Sinema and Republican Vernon Parker are in a near dead heat.
Both Parker and Sinema acknowledged the wait would be long, and Parker urged his supporters to be patient because thousands of ballots remained uncounted.
In northeastern Arizona's 1st District, Republican Jonathan Paton's slight lead over Democrat Ann Kirkpatrick diminished as Tuesday night wore on.
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