This year’s open-seat race for governor of Michigan took off in a new and unpredictable direction Tuesday as John Cherry — the two-term lieutenant governor and presumed front-runner for the Democratic nomination — pulled out of the race.

Cherry, though he never officially announced his candidacy, was regarded as certain to run, and his decision not to leaves the Democratic field in flux. But a number of Democrats had suggested in recent months that a fresh face might make a stronger nominee than Cherry, who politically has gotten the worst end of the job of lieutenant governor.

Cherry, like many of his lieutenant governor peers across the nation, has had too low a profile to build a strong statewide personal following. But at the same time, he has been hurt by the sharp decline in popularity of the term-limited incumbent, Democrat Jennifer M. Granholm, whose job approval ratings have been damaged by the deep economic problems of a state that depends heavily on the struggling auto industry.

Cherry, in a statement released around noon local time Tuesday, attributed his decision to disappointing fundraising results.