U.S. Rep. Juan Ciscomani leads by just 86 votes over Kirsten Engel

Republican U.S. Rep. Juan Ciscomani's lead over Democratic challenger Kirsten Engel is now just 86 votes, unofficial results show.

After trailing Engel in early results from Tuesday's election, Ciscomani took a 417-vote lead late Wednesday afternoon in Arizona's 6th congressional district, which shrunk to 86 by Thursday evening.

With about 175,000 votes left to count in the district, the race is too close to call.

The swing district, which includes portions of the Tucson area, has voters in five counties: Pima, Cochise, Graham, Greenlee and Pinal.

Engel is a former state senator who was narrowly defeated by Ciscomani in the same district two years ago.

Unofficial results have been released since Tuesday night to the Arizona Secretary of State's Office's results page .

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