Massachusetts Republican activists - conservatives and moderates alike - are solidly behind the reelection efforts of President Ronald Reagan. The Bay State GOP, however, is not the big happy family such solidarity may suggest.
At a time when the party's survival as more than a group of political handwringers depends on members pulling together, old rivalries in leadership have surfaced anew.
At issue is the GOP state chairmanship for the next four years. Andrew Natsios, who has held the post since April 1980, is eyeing a new term. Though Mr. Natsios appears to have broad-based support among prominent Republicans statewide, his bid to retain the party gavel is by no means assured.
John R. Lakian of Westwood, the investment counselor who made a bid for the party's nomination for governor two years ago, has his immediate sights set on the GOP chairmanship. He is being aided by Republican National Committeeman Gordon Nelson, from whom Natsios wrested the GOP state committee reins four years ago.
Although the showdown vote won't come until late April, the March 13 state presidential primary may foreshadow the outcome. Next Tuesday, all 80 seats on the Republican State Committee will be filled by GOP voters across Massachusetts , and the 40 men and 40 women chosen will pick their chairman within the next six weeks.
That is why both Natsios and Lakian are busily moving within Massachusetts Republican circles to build grass-roots support among state committee candidates.
In several of the 40 Massachusetts senatorial districts, from which GOP state committee members are elected, candidates committed to Lakian and those pledged to Natsios are pitted against one another. Ballot contests are especially keen in several districts where those who have served for the past four years are not running for a new term.
While acknowledging that a little competition can be a good thing, some prominent Republicans are concerned that such a challenge at this time will only weaken the GOP.
Presumably that is something Lakian and his supporters want to avoid, as determined as they are to reshape the state Republican cause according to their liking.
But in a letter to would-be state GOP committee members, state Sen. David H. Locke of Wellesley suggests that a change in leadership, however well-intentioned, may not be in the best interest of the party in Massachusetts. The carefully worded communique endorsing the Natsios reelection warns that the state GOP ''cannot afford to change horses six months before the 1984 election.'
The party leaders are apprehensive that with no GOP presidential primary contest on next Tuesday's ballot, thousands of Republicans will stay home. This, it is felt, could boost prospects for electing state committee members who are committed to a new state leadership.
Natsios boosters say it is important for a cross section of the Massachusetts GOP to take part in the primary vote and, in the process, to demonstrate wholehearted support for President Reagan.
Senator Locke, a highly respected conservative legislator and the assistant Senate Republican floor leader, is Bay State chairman of the Reagan-for-President Committee in Massachusetts. Under the banner of the Lincoln Coalition, Locke and 65 prominent party members, most of them current or former officeholders, urged state committee candidates to ''join us, please, in building on the foundation that has been laid.''
Joining in the call for keeping Natsios at the helm are all six of Locke's GOP colleagues in the Senate and 18 of the 30 House Republicans who now serve with Natsios. The party's gubernatorial nominees in 1978 and 1982 - former House minority leader Francis W. Hatch Jr. of Beverly and former state Rep. John W. Sears - are also on the bandwagon to retain Natsios as chairman.
It's uncertain whether a leadership change would spur election of more Republicans to public office. A new party chieftain needs time to get things rolling, and time may not be something Lakian would have if he again reaches for the governorship a year or so after winning the GOP gavel.
The likelihood that Lakian would use the GOP chairmanship as a steppingstone toward forging a gubernatorial campaign could make his bid for the party helm more difficult. The case might be different if he pledged to stick around for the full term and forget about becoming governor. There is nothing to suggest Natsios has any intention of seeking an office beyond that of state representative, a post he has held for the past decade.
Lakian and his boosters are sharply critical of the number of local, county, and state legislative seats which have gone uncontested by the GOP. Lakian largely blames the current leadership for much of this, asserting that the GOP must do a better job lining up candidates for all offices if the Republican Party is to make a comeback in the commonwealth.
While thinning ranks continue to concern GOP activists, including Lakian, the slippage did not begin or even accelerate under the current chairman. The Republican percentage of the electorate is about the same as it was when Natsios took over the leadership.
Natsios and his supporters are encouraged by what they call ''increased momentum'' toward the party's rebound, including slight gains in the number of Republicans elected to municipal and legislative seats.
Whatever its shortcomings, there is little doubt the Republican Party hierarchy here is better organized and better funded today than it has been. Annual gross income increased from $206,000 in 1979, the last year under the previous regime, to $476,000 in 1983. The state GOP is in trying to raise $1 million this year to bankroll what Natsios and his supporters hail as ''an aggressive 1984 strategy.''