"All the supporters, I just thank them and appreciate their support," said Unger, who had raised at least $150,000 for his campaign.
The three-term lawmaker and state Senate Transportation & Infrastructure Committee chairman was considered the leading contender to win the Democratic Party's nomination in the May 13 primary election, party chairman Nick Casey said Saturday.
"I'm just kind of surprised" by Unger's announcement, Casey said. "It was not something I had any expectations of."
Kanawha County Democrats Thornton Cooper and Richard A. Robb remain in the 2nd District race, according to West Virginia Secretary of State Betty Ireland's office.
The winner of the Democratic primary is expected to run against Capito, who did not have an opponent in the Republican Party primary as of Saturday.
National Democratic Party leaders had targeted Capito's seat in the upcoming election, said Casey, adding that Unger had their support.
While putting a possible congressional campaign on hold, Unger said his travels in the sprawling 18-county district better equipped him to tackle state and regional issues, which he says are more pressing than ever given the faltering national economy.
"It's going to hit West Virginia harder than other states," Unger said, stressing the need for state leaders to take steps to soften the blow.
Instead of being on the campaign trail for the next several months, Unger said he could make better use of his time tackling challenges in the Eastern Panhandle and providing some senior leadership to a tri-county delegation in transition.
Fellow 16th District state Sen. John Yoder, R-Jefferson, decided to run for a judgeship in the 23rd Judicial Circuit rather than seeking another four-year term.
Casey also confirmed Saturday that Del. Locke Wysong, D-Jefferson, had decided not to seek re-election. Wysong was expected make an official announcement, but could not be reached Saturday.
"Locke's been a great delegate," Casey said. "We'll very much miss him."