BOSTON A new congressional map would lump two members of the state’s all-Democratic delegation into a single district, creating one new district without an incumbent.
The proposed map, unveiled Monday by the Legislature’s Redistricting Committee, would also create the state’s first true “minority-majority” district, in which minority groups compromise a majority of the voting age population.
The new districts reflect the loss of one of the state’s 10 seats in the House, due to population shifts measured by the most recent U.S. Census. The map must still be approved by the full Legislature and signed by Gov. Deval Patrick.
The plan would place U.S. Reps. Stephen Lynch of South Boston and William Keating of Quincy into a new district by pulling Quincy into the district currently represented by Lynch.
Keating, a freshman, whose family owns a home on Cape Cod, would have the option of running in a newly formed district that includes the Cape — which Keating currently represents — and parts of southeastern Massachusetts.
Keating could not immediately be reached for comment.
The proposed map makes major changes in western Massachusetts by essentially carving up the current 1st District, now represented by Rep. John Olver, who recently announced that he would retire at the end of his term.
Berkshire County would be folded into a new district with Springfield, currently represented by Rep. Richard Neal.
Rep. James McGovern of Worcester would reside in a district that would stretch north to pick up portions of Franklin and Hampshire counties, and south to the Rhode Island state line.
Advocates for minority voters cheered the committee’s creation of the redrawn Boston-area district now represented by Rep. Michael Capuano of Somerville.
Carving out a true minority-majority district was a state goal of the redistricting panel.
“I’m pleased with the fact that we have been able to increase the number of minorities both racially and ethnically in this congressional district, and do it by essentially reflecting the movement of people of color into Boston and around Boston,” said Rep. Byron Rushing, D-Boston, a member of the committee.
Massachusetts saw its Latino and Asian-American population each jump 46 percent over the last 10 years. The state’s black population — mainly driven by immigrants from Haiti — saw a rise of 26 percent, while the white population fell by 1.9 percent, according to data from the 2010 census.
The newly created district, where no incumbent currently resides, would include Cape Cod, Plymouth, New Bedford and part of Fall River.
Rep. Barney Frank, whose district currently stretches from the affluent Boston suburbs of Newton and Brookline to southeastern Massachusetts, would lose New Bedford but retain part of Fall River, which is split in the new map.
The proposed map also preserves the heavily Democratic Lawrence in the district now represented by Rep. Niki Tsongas of Lowell.