Retired Maine Supreme Judicial Court Justice Donald Alexander chaired Maine's bipartisan redistricting commission that agreed on new congressional and legislative maps. Credit: Robert F. Bukaty / AP

AUGUSTA, Maine — The Maine Legislature is poised to vote today on new legislative and congressional maps that will account for the recent population shifts and shape the state’s politics for the next decade.

Maine is set to become just the second state to finalize its new districts after Oregon passed maps earlier this week. Although a delayed census shortened the time period for the Legislature’s bipartisan commission to act, lawmakers ultimately reached deals on legislative and congressional maps at the last minute — including a deal on Maine Senate maps on Monday, the commission’s final day of work.

Just shy of 54,000 Mainers — all in Kennebec County — will find themselves living in a new congressional district next year, while tens of thousands of others will be in a new Maine House or Senate district. Here are five major takeaways from the new maps.

Congressional map fairer than most states

Gerrymandering — or drawing maps that give one party an extreme electoral advantage — has dominated the national conversation on redistricting. That was not the case in Maine.

Although there are fewer ways to gerrymander with only two districts, the commission’s decision to only move towns within Kennebec County, coupled with the need to draw maps that would receive a two-thirds vote in the Legislature, meant Republicans and Democrats’ proposed districts were relatively similar. The final compromise is only marginally different from either proposal, and from the current maps, in terms of its partisan outcome.

Analysts and advocates have come up with different ways to assess whether maps favor one party or the other. One metric developed by academic researchers and used by the site FiveThirtyEight is known as the “efficiency gap,” and attempts to assess the competitiveness of districts by looking at how many votes were cast that each party did not need.

For Maine’s final proposed congressional map, the efficiency gap is 6.4, which is lower than the majority of the map proposals in other states tracked by FiveThirtyEight. While some states may ultimately draw more efficient maps, the most gerrymandered maps after the 2010 census had efficiency gaps higher than 25, so Maine stacks up rather well.

A compromise put Augusta in Maine’s 2nd District

The capital city of Augusta has been in Maine’s 1st District ever since Maine dropped from three congressional districts to two after the 1960 census. But this year’s census numbers required moving about 23,000 people from the 1st District to the 2nd District.

The commission agreed early on to only make changes within Kennebec County, the one county currently split between districts. Within that framework, it was all but impossible to draw equally populated districts without moving over Waterville or Augusta, the county’s two largest cities.

Waterville was in the 2nd District before, including in the 2000s. But Republicans strongly resisted moving over the city, which is the home to two small colleges and a place that President Joe Biden and Rep. Chellie Pingree, both Democrats, won by nearly 30 points in 2020.

Augusta still leans slightly toward Democrats, with Biden and Pingree winning by 11 and 15 points respectively last year. But that is more palatable to Republicans, so the capital city landed in the 2nd District in the final compromise. Chelsea, Farmingdale, Hallowell, Manchester, Readfield and Winthrop are also moving to the 2nd District, while Albion, Benton, Clinton, Litchfield, Unity township and West Gardiner move from the 2nd District to the 1st.

A new Senate district in southern Maine could favor Republicans

Maine’s population growth over the past decade was driven by Cumberland and York counties, both of which saw their populations increase by more than seven percent since 2010. The region has also grown more liberal — in 2010, Democrats had about 34,000 more registered voters in those two counties than Republicans, according to data from the secretary of state’s office. In 2020, that figure was nearly 77,000.

Republicans currently hold only one Senate seat in York and Cumberland counties, a district held by Sen. David Woodsome, R-Waterboro. But the new maps all but ensure they will maintain a presence in southern Maine, as registered Republicans outnumber Democrats by about 2,300 voters in a new district encompassing parts of York, Cumberland and Oxford counties.

Republicans also stand a chance of hanging onto the district currently held by Woodsome, who is term-limited. In terms of voter registration, Democrats will outnumber Republicans by about 200 people in the new district, which includes Sanford, Waterboro, Alfred and Lebanon. It could be one of several battleground districts next year.

Rural counties with declining populations see less representation

The commission largely attempted to keep individual counties together for Maine Senate Districts, following guidance from previous redistricting processes about avoiding crossing political subdivisions where possible and keeping communities of interest together.

But population declines in rural counties make that harder, and several counties will see their political power decline under the new maps. Because Senate districts must be within 5 percent of the average district population of just over 38,900, the district encompassing Washington County — which previously included three Hancock County towns — will add 10 more towns and several unorganized territories from Hancock County.

Piscataquis County saw its population drop to 16,800 in the most recent census, accounting for only 40 percent of the population in its new district, which also includes a handful of towns northwest of Bangor. The district will still be heavily conservative and is likely to be represented by Sen. Stacey Guerin, R-Glenburn, if she opts to run for reelection. But that would mean there would be no members of the Maine Senate from Piscataquis County.

The district represented by Senate President Troy Jackson, D-Allagash, is still entirely within the bounds of Aroostook County. But the second Aroostook District, represented by Sen. Trey Stewart, R-Presque Isle, will draw about a quarter of its population from Penobscot County, up from about 5 percent under the previous configuration.

House maps reflect changes in fast-growing towns

Maine’s fastest growing towns found themselves split across more House districts, as the average district size grew slightly to just over 9,000 people. Topsham, which used to be a single district, grew by 8.8 percent over the past decade, and is now split across two districts. Westbrook, which saw its population grow by 16.6 percent over the past decade, is now divided across three districts instead of two. 

Freeport, which grew by 10.9 percent, is now its own district, no longer including part of Pownal. Nearby Yarmouth likewise got its own district after growing by 7.7 percent over the decade, no longer sharing representation with Chebeague Island and Long Island.