Boston ? A Republican can be elected governor of the bluest state. Indeed, Republicans have held the statehouse here since Michael Dukakis’ last year, 1990. Mitt Romney is the inexplicably happy holder of it now. What kind of person is preternaturally cheerful while governing with a Legislature in which 34 of 40 senators and 139 of 160 House members are Democrats?

“My vetoes count for nothing,” he says cheerfully. But, then, he seems to relish heavy political lifting, as in his 1994 race against Sen. Ted Kennedy, which was Kennedy’s closest race (58-41) since his initial election in 1962. Politics, says Romney, 57, is “kind of like sport for old guys.” In Massachusetts, “I’m not supposed to win, but occasionally when the puck goes into the net you feel pretty good.” He has done, or facilitated the doing of, some fine things, such as scrapping the Clean Elections Act, the Massachusetts mishmash of public funding and limits on political contributing and spending that was, Romney says, “designed to protect incumbency in the most extreme manner.”

Willard Mitt Romney (his first name honors his father’s friend, J. Willard Marriott, the hotelier) is the son of a presidential candidate, George Romney, Michigan’s governor, 1963-69. His 1968 presidential campaign fizzled early, but President Nixon made him secretary of housing and urban development.

Mitt, born in 1947, is a devout Mormon who attended Brigham Young University, then did the four-year program that earns both business and law degrees at Harvard. He graduated cum laude from the law school and in the top 5 percent of his business school class that included a future president’s son given to wearing a Texas Air National Guard flight jacket.

As a venture capitalist, Romney earned a fortune helping build such companies as Staples and Domino’s Pizza. In 2002, he rescued the Salt Lake City Winter Olympics from scandal and financial mismanagement and later that year was elected governor, facing a $3 billion gap in a $22 billion budget. By July 2004 there was a more than $700 million surplus, achieved without tax increases. Thanks partly to a 2000 referendum that cut the state income tax from 5.95 percent to 5.3 percent, Massachusetts now ranks 14th among the states for the lowest state and local tax burden.

A strong supporter of charter schools — Romney vetoed the Legislature’s attempt to freeze the number of them — he finds, as education reformers always do, that the teachers unions are the impediment. In the political competition in a one-party state, he says, primaries are “everything.” Public employees unions are crucial in primaries, so elected officials wind up negotiating with those who, in effect, elected them.

On national issues, he says: “You can’t maintain, over time, a tier-one military with a tier-two economy” — and a tier-one economy depends on higher education. He notes that a few miles away at MIT, 36 percent of the graduate students are from abroad, which is fine — unless it indicates that American students are lagging in interests or aptitudes.

In the 44 years since Massachusetts provided the last U.S. senator elected president, 35 sitting senators have sought, with varying degrees of seriousness, presidential nominations. Both parties know that governors are better bets. Romney’s disadvantage will be that, given his Legislature, he has had no real opportunity to advance a conservative agenda.

However, thanks to the state’s Supreme Judicial Court, he lives at ground zero in the same-sex marriage debate, and he has pleased social conservatives by opposing resolution of the debate by judicial fiat. He endorses “moral federalism” — the right of each state to legislate its own consensus — but testified before Congress in support of an anti-same-sex marriage amendment to the U.S. Constitution.

Until recently, he has not been raising money at a clip that indicates a firm commitment to seek re-election in 2006. He says he anticipates running again but if he wants to be in the 2008 presidential mix, he might benefit from a Washington job with national security dimensions. His Olympics experience was good training for future secretary of homeland security.

In Massachusetts, both senators and all 10 members of Congress are Democrats, and in the last ten 10 presidential elections voters have favored Democratic candidates by a higher average — 16 points — than any other state. Strange but true: Massachusetts is an unlikely place to discern a potential Republican presidential aspirant, but on recent evidence (1988, 2004) it is a ruinous source of Democratic presidential nominees.

— George Will is a columnist for Washington Post Writers Group.