Democratic incumbent Ann Kirkpatrick was still locked in a tight battle against Republican rival Andy Tobin Wednesday in Arizona’s 1st Congressional District, a day after midterm elections that saw the GOP take the U.S. Senate majority for the first time in six years closed across the nation. Arizona unofficial election results showed Tobin with 46 percent of the vote against Kirkpatrick's 53 percent, a difference of roughly 10,000 votes. 

Tobin, 56, was first elected to the Arizona House of Representatives in 2006, and was elected House speaker in 2011. Like other Republicans in the 2014 national races, his campaign focused on tying Kirkpatrick to President Barack Obama's Affordable Care Act. Kirkpatrick, 64, in turn, criticized Tobin for excessive spending cuts in education and welfare services. She first won the district seat in 2008, but lost in 2010 to Republican Paul Gosar. But after Gosar moved to the 4th District, Kirkpatrick regained the position in 2012 by 10,000 votes.  

The New York Times called the House district, which covers much of the eastern, rural parts of the state, “one of the most competitive districts in the country.” Roughly 37 percent of voters in the district are registered as Democrats, compared to 32 percent independents and just 30 percent Republicans, according to Arizona Public Media.  

An important demographic is the Navajo community. A large part of Kirkpatrick’s 2012 win was due to redrawn district lines that included the Navajo and other reservations. In an October debate, both candidates agreed on the importance of increased support to the Navajo Nation, a key demographic.

“Let’s not forget 2012,” Kirkpatrick’s spokesman D.B. Mitchell told the Arizona Capitol Times. “Everyone thought Ann had lost, until the Navajo vote came in and she gained thousands of votes that ultimately led to her decisive victory.”

The competition was one of the four most expensive U.S. House races in the country. In 2014, Kirkpatrick spent $6,025,095 on her campaign, while Tobin spent $5,928,524, according to the Center for Responsive Politics.

“There are only so many districts in the country that are truly competitive. And we happen in this case in this cycle to have two of them,” analysts from FirstStrategic Communications told The Arizona Republic, which endorsed Kirkpatrick.

Tobin was born and raised in New York City before moving to Arizona in 1979.