Because of that, there's a bitterness to his legacy in a state that has an outsized sense of its own importance and a no-compromise commitment to litmus-test liberal politics.
Massachusetts was a means to an end for Romney. For other Bay State pols, Massachusetts is an end in itself even for those with eyes on the same prize as Romney. John Kerry lost his presidential bid, and eight years later, he's still in the Senate, hosting hearings for Gloucester fishermen.
Romney left office to run for president, and never looked back. Massachusetts may see him as a user and betrayer.
But, like it or not, Massachusetts is where it all began for Romney. He earned law and business degrees at Harvard, raised a family in Belmont, and built a business at Bain. It was in Massachusetts that he began constructing and deconstructing the political persona that is hard because of all the shifting to pin down to this day.
Romney lost a 1994 bid for Senate when he challenged the late Edward M. Kennedy, a Democratic icon. He came back from that defeat to win the only general election he has ever won, the one that made him governor of Kennedy Country.
Romney's gubernatorial victory occurred in a state where Republicans account for only 12 percent of registered voters. His success back in 2002 is often attributed to the weakness of his Democratic challenger.
But it was also a testament to a carefully calibrated centrist message that has a history of resonating with independent or unenrolled voters.
Romney pitched fiscal conservatism, insisted he supported Roe v. Wade, and let his campaign hand out fliers at a gay pride parade. In doing so, he tapped into a comfort zone with voters that helped a series of Republican candidates win the governor's office.
Unlike his predecessors, Romney also attempted the thankless task of trying to rebuild the state's Republican Party, a feeble institution built on "chicken wire and duct tape," as longtime Democrat and onetime Boston City Councilor Michael McCormack puts it.
To further the GOP cause in Massachusetts, Romney recruited more than 100 candidates to challenge Democratic lawmakers. When all those Republican candidates lost, Romney declared, "From now on, it's me-me-me." And from then on, it was.
He proposed health care reform legislation because he believed it would bolster his national ambitions. For the same reason, he made a hard right turn on social issues.
As he fought for credibility with Republican primary voters, he abandoned the middle ground on wedge issues like immigration and walked away from the health care reform act that Bay State Democrats still consider his major accomplishment.
As a presidential candidate, Romney is unpopular in Massachusetts. According to the Real Clear Politics polling average, President Obama leads Romney by 18 points here. Compare that with polling data for Republican Sen. Scott Brown, whose race with Democrat Elizabeth Warren is considered a toss-up.
In the state Romney left behind, even Republicans use words like data-driven and soulless to describe him.
Like Democrats, they respect Romney's intelligence but detest his unabashed opportunism. They don't want to be quoted saying that, because he could be the next president.
Romney's campaign headquarters is located in the North End, and the national press refers to "Boston" when official statements emanate from there.
But from the Massachusetts perspective, there's little to connect Romney to the city on the hill, given the dominance of Democrats and the major role Gov. Deval Patrick is playing in advancing Obama's re-election.
Massachusetts is a place he passes through, not a place that calls him home. Yet for Romney, it could be the stepping stone to the White House that others before him have tried so hard to make it.