Arizona voters on Tuesday will pick a female senator for the first time in state history to replace the retiring Republican Sen. Jeff Flake, decide whether GOP Gov. Doug Ducey gets a 2nd term in office and if the state's private school voucher program should be expanded.
Nearly 1.5 million early ballots had been received by county elections officials as of Friday. That's about 40 percent of the state's registered voters. Total turnout is estimated to top 56 percent, an unusually high number for a midterm election. Only 36 percent of registered voters cast ballots in 2014.
Polls open at 6 a.m. Tuesday and close at 7 p.m.
Here's a look at the top races:
TIGHT SENATE RACE
The race to replace Flake has been a knock-down, drag-out fight between Democrat Kyrsten Sinema and Republican Martha McSally that could go either way.
The contest between the two sitting congresswomen is considered one of the nation's most competitive, with more than $90 million in spending by candidates and outside groups.
Sinema paints herself as an "independent" centrist who can work across the aisle and has backed President Donald Trump's initiatives more than 60 percent of the time. The three-term congresswoman currently represents parts of Phoenix and Tempe.
McSally has focused on border security and boosting the nation's military while attacking Sinema as too radical for Arizona. She is a former Air Force pilot who has served two terms representing a Tucson-area congressional district and has run as a strong Trump backer after being criticized during the primary for not being supportive enough of the president.
Ducey appears well-positioned to win a second term despite a teacher strike that shut down public schools across the state earlier this year. The Republican has vastly outspent Democratic challenger David Garcia, an Arizona State University education professor. Polls show Ducey with a healthy lead.
The teachers returned to class after Ducey signed a plan for teacher pay raises that will reach 20 percent by 2020, including 1 percent granted in a previous budget.
Garcia backed the strike that shut down public schools for nearly a week in May amid demands for higher teacher pay and more public education funding.
Garcia refused to accept lobbyist or corporate contributions and his campaign was outspent by Ducey many times over, including millions of dollars in ads by the Republican Governors Association attempting to show Garcia as weak on border security.
Arizona Democrats hope to pick up a seat in the state's nine-member congressional delegation by winning the Tucson-area 2nd District now held by Republican Martha McSally. She won the seat in 2014 by a narrow margin and broadened her victory in 2016. The district had previously been held by Democrats.
Former Rep. Gabby Giffords held the seat until she resigned after an assassination attempt in Tucson in 2011 and was replaced by Democrat Ron Barber in 2011. He won a full term in 2012 but narrowly lost to McSally in 2014.
This year's 2nd District races features Democrat Ann Kirkpatrick and Republican Lea Marquez Peterson.
The 1st and 9th Districts are also seen as competitive and currently held by Democrats. Incumbent Tom O'Halleran is being challenged by retired Air Force officer Wendy Rogers to represent the 1st District, while former Phoenix Mayor Greg Stanton holed to replace Sinema and represent the 9th District. He faces Dr. Steve Ferrera, a physician.
There is a rematch between Republican Rep. Debbie Lesko and Democrat Hiral Tipirneni in the 8th District in the north and west Phoenix suburbs. Lesko beat Tipirneni by less than 5 percentage points in an April special election to replace former Republican Rep. Trent Franks.
Voters are being asked to accept or reject a massive expansion of the state's private school voucher program that was adopted by the GOP-controlled Legislature and Republican Gov. Doug Ducey last year.
The measure, known as Proposition 305. is on the ballot because a grassroots group of educators objected and used a provision in the state constitution to put it on hold by collecting signatures. A yes vote allows the expansion, while a no vote rejects it.
Opponents of Empowerment Scholarship Accounts say they mainly benefit wealthy Arizonans who will send their children to private school anyway while siphoning cash from public schools.
Backers say they help parents from all income levels and give families a choice in where to send their children to school.