The Massachusetts GOP was left in its worst shape ever after Romney's four years as well:
Romney's dismal record as the Republican leader in Massachusetts
Romney pledged to build the Massachusetts Republican Party, but in fact he did almost nothing. During his tenure there were two elections for the entire Legislature (2004 and 2006). In each election the Republicans lost seats. Republicans now hold the fewest seats in the Legislature since the Civil War.
During the four years of Romney's tenure, the number of registered Republicans in Massachusetts fell by 31,000. During that same period, the Massachusetts Democratic Party gained 30,000. - Boston Globe 11/2/2006
In the 2006 elections, most offices were not even challenged by Republican candidates. In the November general election for the six statewide Massachusetts constitutional offices there were more Green-Rainbow Party candidates on the ballot than Republicans!
The party's slide has been so precipitous that Republicans yesterday did not contest 130 of 200 legislative seats, fielded a challenger in only three of 10 congressional districts, and put up fewer candidates for statewide office (three) than the Green-Rainbow Party (four). - Boston Globe, 11/8/2006
In 2006, while Romney was chairman of the National Republican Governors Association - a group dedicated to electing more Republican governors - his own hand-picked Republican successor as governor lost badly to the Democrat, despite the fact that Republicans have held the governorship in Massachusetts since 1990. Romney largely ignored the Massachusetts elections and spent most of the time during the campaign out of state building his presidential campaign. He came back and publicly campaigned for the Republican candidate the day before the general election!
"Locally, this is a rebuke to Mitt Romney and checking out within six months after being elected and having accomplished almost nothing," said [Jim] Rappaport [former chairman of the state Republican Party]. - Boston Globe, 11/8/2006
"Romney arrived on the scene with great promise, but is leaving the Republican Party here in shambles. Not only are the Republicans yielding the governor's office for the first time in 16 years, but registered Republicans have fallen by 31,000 since Romney took office, and their legislative presence is at historic lows. But it worked out fine for him: He is now chasing the prize he really covets, the presidency." - Boston Globe 11/8/2006
"The Massachusetts Republican Party died last Tuesday. The cause of death: failed leadership. The party is survived by a few leftover legislators and a handful of county officials and grassroots activists who have been ignored for years. Services will be public and a mass exodus of taxpayers will follow. In lieu of flowers, send messages to New Hampshire Republican voters warning them about a certain presidential candidate named Romney." - Boston Herald, 11/12/2006