Businessman Eric Wnuck (R) has dropped out of the primary to face Rep. Harry Mitchell (D-Ariz.).

Wnuck made news in the third quarter when he announced a strong $160,000 raised. He saw his fundraising fall off significantly in the fourth quarter, though, and he said he needs to focus on his business.

"As many of you can understand, this is a tough economy and we all have been affected," he said in a statement. "I too have been impacted and need to concentrate on protecting my business and all of my employees whose jobs and families depend on its success. But most importantly, I must focus on what has always been my first priority, my family."

Wnuck also threw his support behind businessman Jim Ward, who faces a pair of repeat candidates in the primary: 2008 nominee David Schweikert and runner-up Susan Bitter Smith, who launched her campaign last week.