Next to the reelection of President Ronald Reagan, national Republican leaders would like nothing better than to win the US Senate seat of retiring Democrat Sen. Paul E. Tsongas of Massachusetts.
President Reagan is not likely to inject himself into the state primary contest for the GOP senatorial nomination between Elliot Richardson and Raymond Shamie. But national Republican strategists, including a number of conservatives , apparently feel Mr. Richardson would have the best chance of winning Nov. 6.
They are not satisfied to simply accept the nominee who emerges from the Sept. 18 primary and hope for the best. They want to see a Republican elected from Massachusetts and they know that a strong turnout for the GOP Senate candidate could help the President pull off a minor political miracle - carrying one of the most liberal states in the Union twice.
Particularly pleasing to those in the White House would be having the state of Sen. Edward M. Kennedy, US House Speaker Thomas P. O'Neill Jr, and Gov. Michael S. Dukakis, three of the nation's most strident Reagan critics, with a Republican in the Tsongas seat.
Already it has been made clear that the national GOP organization is ready to put considerably funding behind a Richardson candidacy. And, although endorsements by out-of-staters aren't likely to carry much weight with Massachusetts voters, Richardson has been endorsed by 28 Republican US senators including assistant GOP floor leader Ted Stevens of Alaska, a conservative whose views on most issues might be closer to those espoused by Mr. Shamie.
Ideologically, President Reagan would doubtless be more comfortable with fellow conservative Shamie, the millionaire industrialist who has gone out of his way to embrace the President's views.
Richardson and Shamie are as different in political philosphy as they are dissimilar in style.
Basic to the Richardson appeal within national GOP ranks is his high visibility and reputation for integrity built up through the years. That was most evident when, in October 1973, he resigned as US attorney general rather than obeying President Richard Nixon's order to fire Archibald Cox as special prosecutor in the Watergate scandal.
The primary contest between Richardson and Shamie may be too close to call. But most voter-preference samplings involving Democrats and independents as well as Republicans indicate that Richardson would be the stronger against the Democratic nominee.
Self-made businessman Shamie, who has plowed close to $750,000 of his own money into his campaign, is considerably rankled by the financial and other support the Richardson effort has been getting from members of the GOP whom Shamie hoped would back him, or at least remain neutral.
An enthusiastic backer of the platform adopted at the Republican National Convention in Dallas last month, Shamie is banking heavily on the votes of Bay State GOP loyalists, especially those who share his ''no new taxes'' position.
By contrast, Richardson, a political moderate whose three-decade government career has included five federal cabinet posts, refuses to commit himself to oppose more taxes. Instead of taking a deep breath and accepting the Republican platform, the Harvard-educated Yankee from Brookline openly denounced the document as something he could not in conscience support.
How many votes in the primary this bold move may have cost Richardson is uncertain. It might be noted, however, that many - indeed most - of those this might offend are archconservatives who probably long since were on the Shamie-for-Senate bandwagon and unlikely to jump off.
If nothing else, the Richardson denunciation may have further polarized opposition segments within the Bay State GOP. At the same time, it could further boost his stock as a moderate who is not about to become a rubber stamp for something in which he does not believe. That could be very helpful in attracting independent and Democratic votes the GOP candidate must have to win on Nov. 6.
There is no doubt that the name on the other side of the ballot will belong to a Democratic liberal, probably either Lt. Gov. John F. Kerry or US Rep. James M. Shannon.
Secretary of State Michael J. Connolly, a moderate-to-liberal Democrat, is considered a long shot for the nomination.
Holyoke Community College president David M. Bartley, who fits the conservative mold on fiscal matters, is hoping to attract Democrats responsive to his pledge to hold the line on taxes.
Mr. Bartley, former speaker of the state House of Representatives and later secretary of administration and finance for conservative Democratic Gov. Edward J. King, is the only senatorial hopeful in either party from outside eastern Massachusetts. He has had a difficult time time putting his campaign accross.
Richardson and Congressman Shannon appear to have won the most impressive endorsements in their respective Senate primary races.
Shannon has become a protege of Speaker O'Neill, whose early endorsement was certainly not a liability in the quest for campaign funds.
Senator Tsongas has made it clear he would remain on the sidelines until after the Sept. 18 vote. Gov. Michael S. Dukakis and US Sen. Edward M. Kennedy, the commonwealth's two other leading Democrats, are unlikely to take sides until after the primary.
For Mr. Kerry, a ''he's my man'' pronouncement from the governor, the man with whom he serves in the state's executive branch, would have been especially welcome. But what may have been a greater disappointment to the lieutenant governor and former national leader of Vietnam Veterans Against the War was the endorsement of Shannon by Vietnam war veterans' groups.
However, it is doubtful that voters of either party in Massachusetts are much swayed by endorsements.