The race to fill the vacancy in Congressional District 8 is between Democrat Ron Barber, Republican Jesse Kelly and Green Charlie Manolakis.
Voters have until 7 p.m. to weigh in on who should represent them in Congressional District 8.
Those who already sent in a mail-in ballot accounted for 38 percent voter turnout in Pima County, before polls even opened for in-person voting this morning.
Pima County residents make up 80 percent of the voters in the district, which also includes all of Cochise County and parts of Santa Cruz and Pinal counties.
Democrat Ron Barber, Republican Jesse Kelly and Green Party candidate Charlie Manolakis are competing in the race to represent the district. Gabrielle Giffords resigned from the seat in January, during her third term in office. She continues to recover from the January 2011 assassination attempt that left six people dead at one of Giffords' constituent events on the Northwest side of Tucson.
The winner of today's election will serve out the remainder of Giffords' term, which runs through early January 2013.
It's too late to mail in an early ballot, but voters can cast ballots in person at their designated poling places or hand-deliver completed early ballots to any polling place. To find out where to vote in Pima County, visit the Recorder's Office website.
The race has largely focused on the future of Social Security, Medicare and the Affordable Care Act.
Still trying to decide how to vote? Watch a forum with the candidates, or read a transcript of the candidates' answers to questions on those topics and more.
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