For those keeping track:
Prime Ministers of the Commonwealth of New England
1841-1855: Daniel Webster (Conservative)
def '41: Francis Granger (Liberal)
def '44: John Davis (Liberal), Pierre Soulé (Radical)
def '47: John Davis (Liberal), Pierre Soulé (Radical)
def '50: John Brown (Radical), Franklin Townsend (Liberal)
def '52: John Brown (Radical), John Hale (Radical-Liberal), Franklin Townsend (Liberal)
1855-1856: Franklin Pierce (Conservative)
1856-1859: John Hale (Liberal)
def '56: Franklin Pierce (Conservative), Lafayette Foster (Radical)
1859-1861: Stephen Douglas (Conservative)
def '59: John Hale (Liberal)
1861-1863: A. Oakley Hall (Conservative)
1863-1874: Charles Adams (Liberal)
def '63: A. Oakley Hall (Conservative)
def '66: William Barnum (Conservative)
def '70: Benjamin Hotchkiss (Conservative)
1874-1877: Roscoe Conkling (Conservative)
def '74: Abner McClenan (Liberal)
1877-1884: Lyman Trumbull (Liberal)
def '77: Roscoe Conkling (Conservative), Alonzo Draper (Workingmens')
def '80:
1884-1887: Levi Morton (Conservative)
def '84:
1887-1890: Rutherford Hayes (Liberal)
def '87:
1890-1905: Levi Morton (Conservative)
def '90:
def '94:
def '98:
def '02:
1905-1916: Henry Lodge (Liberal)
def '05:
def '09:
def '12:
1916-1919: Eugene Foss (Conservative)
def '16:
1919-1936: Charles Hughes (Liberal)
def '19:
def '22:
def '26:
def '29:
def '32:
1936-1938: Charles Richards (Conservative)
def '36:
1938-1940: Warren Austin (Conservative)
1940-1945: Angus MacDonald (Labour)
def '40:
def '44:
1945-1947: Chester Bowles (Labour)
1947-1948: Sinclair Weeks (Liberal)
1948-1951: Leverett Saltonstall (Conservative)
def '48:
1951-1955: Felix Hébert (Labour)
def '51:
1955-1958: Prescott Bush (Conservative)
def '55:
1958-1961: Thomas Dodd (Labour)
def '58:
1961-1962: John Notte (Labour)
1962-1969: John Kennedy (Conservative)
def '62:
def '66:
1969-1980: Edmund Muskie (Labour)
def '69:
def '73:
def '76:
1980-1990: George Bush (Conservative)
def '80:
def '83:
def '87:
1990-1993: Chris Dodd (Labour)
def '90:
1993-2001: Lowell Weicker (Conservative)
def '93:
def '97:
2001-2005: John Kerry (Labour)
def '01:
2005-2009: Donald Carcieri (Conservative)
def '05: Madeleine Dubé (Francophone), Shawn Graham (Reform), Barbara Boxer (Socialist Alternative), John Kerry (Labour), Ralph Nader (Green)
2009-2018: Paul Kirk (Labour)
def '09: Donald Carcieri (Conservative), Shawn Graham (Reform), Madeleine Dubé (Francophone), Ralph Nader (Green), Barbara Boxer (Socialist Alternative)
def '13:
def '16: Elinor Carbone (Conservative), Dominic LeBlanc (Francophone), Elizabeth May (Green)
2018-2018: Geoff Regan (Labour)
2018-20??: Elinor Carbone (Conservative)
def '18: Bernie Sanders (Social Democratic), Geoff Regan (Labour), Elizabeth May (Green)