Greaser, 41, exited the race Saturday.
"I had just come to believe I would have been bounced in two years," said Greaser, a married father of two young children. "I just couldn't do that to my family or the clients I have now."
Nixon will appoint a prosecutor to fill the two years left in former Prosecuting Attorney Morley Swingle's term until the 2014 election. Swingle has accepted a position as a federal prosecutor in the U.S. attorney's office.
Greaser became the second lawyer to drop out in the same number of days. Allen Moss, citing professional and political concerns, did so last week. Greaser's exit leaves the field devoid of Democrats for a governor who has picked only Democrats when given the opportunity. Those who remain include private practice lawyer Chris Limbaugh and assistant prosecutor Frank Miller, both Republicans.
Greaser, 41, had only signaled an interest in the job, but he said it was genuine. He was tempted by the thought of becoming the first Democrat to hold the office in more than four decades. Not to spite Republicans, he said, but to win them over.
Greaser said Swingle told him that his was among the names the outgoing prosecutor had recommended to Nixon.
"I sort of saw it as the ultimate experiment," Greaser said. "I feel like I could have stepped in immediately and performed the job admirably."
Greaser also consulted several colleagues. Many mentioned the difficulty of rejoining the criminal defense side after what would amount to a two-year hiatus. Three years ago Greaser opened his own practice, which he said is beginning to thrive.
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