PORTLAND, Maine — The nomination process for the next Cumberland County commissioner from District 3 began this month, two years ahead of schedule.

Last spring, when state legislators reshaped Maine’s House and Senate districts in response to the 2010 U.S. Census, they also reconfigured the state’s county districts and changed the terms of the commissioners who govern them.

District 3 Commissioner Mark Grover, who began his term in January 2013, was elected to serve through December 2016. Now his term will run through December 2014.

Conversely, commissioners whose terms were set to end in 2014, including Neil Jamieson of District 1 and Susan Witonis of District 2, saw their terms extended an additional two years, through December 2016.

The county’s redistricting also puts Grover in the position of being unable to run for re-election, regardless of the timing, because his hometown, Gray, has been moved to District 2.

Three of Cumberland County’s five districts were altered:

• District 1, which includes Baldwin, Bridgton, Gorham, Harrison, Scarborough, Sebago and Standish, lost Harrison to District 2.

• District 2, which now includes Casco, Falmouth, Frye Island, Gray, Harrison, Naples, New Gloucester, Raymond and Windham, lost Chebeague Island, Cumberland, Long Island and Yarmouth to District 3.

• District 3, which now includes Brunswick, Chebeague Island, Cumberland, Freeport, Harpswell, Long Island, North Yarmouth, Pownal and Yarmouth, lost Gray and New Gloucester to District 2.

District 4, which includes Cape Elizabeth, South Portland, Westbrook, and part of Portland, and District 5, which includes most of Portland, remained intact.

“The whole thing was a very political process, and it was about legislators, not commissioners,” Assistant County Manager Bill Whitten said of the redistricting. “The commissioners were so far down on the list of priorities for the state when they did this.”

After the terms of the redistricting were finalized in June, some counties pushed for legislation that would undo the impact on their districts, Grover said, although Cumberland County was not among them.

None of the bills were considered by the Legislature.

“Obviously, I’m disappointed that I will not serve out the term to which I was elected, but I did not go out and speak to any legislators to try and get that changed,” Grover said. “That would’ve been self-serving and probably useless.”

Candidates to be the next commissioner from District 3 — or Districts 4 or 5, where Commissioners Thomas Coward and James Cloutier, respectively, will be up for re-election — have until March 17 to submit the requisite petition signatures in advance of the June 10 primaries; those running as independents will have until June 2. The general election is set for Nov. 4.

After sending an email last week to remind media and constituents about the opening of the nomination process, Grover said, “county government positions tend to be pretty low-key positions, so voters often are not very aware of that particular vote.”

Voters often are not very aware of county government, period.

A layer of representation situated between the local and state levels, county government is often responsible for jails, sheriff’s departments, emergency management agencies, probate courts, deeds offices and district attorneys.

Grover, who works full time as a software engineer for DeLorme in Yarmouth, said that in his final year as commissioner he intends to focus largely on a project with the Cumberland District Public Health Council to provide information and resources to people with mental health and substance abuse disorders. A former Gray town councilor, he said he expects to serve the public again in the future, either as a volunteer or an elected official.

Grover said the changes brought about by redistricting caught him off guard, but perhaps that was for the best.

“I didn’t know until last summer that the state redistricts the county governments as well,” he said. “I’m sort of glad I didn’t know because I probably would’ve been losing sleep over it.”