THE 1988 ELECTION marks a fundamental change in Republican politics: the party is no longer dominated by the ideological division between moderates and conservatives that over two generations pitted Eisenhower against Taft, Goldwater against Rockefeller, Reagan against Ford.

"It's establishment conservatism today," said Lance Tarrance, "The days when there were two challenging factions, those days are over." Tarrance is the pollster for Rep. Jack Kemp (R-N.Y.) who has been conducting an uphill battle to revive the anti-establishment momentum that carried Reagan from his first presidential bid in 1968 through success 12 years later.

While Vice President Bush and, to a lesser extent, Sen. Robert J. Dole (R-Kan.) have cultural and stylistic ties to moderate Republican traditions, all of the four major GOP candidates now support aid to the contras, the Strategic Defense Initiative and additional restrictions on abortions. None is in the tradition of a John Anderson willing, for example, to support the Equal Rights Amendment. "The differences are milliseconds, not miles, and they are all on the right," Tarrance said.

The evolving Republican electorate has produced sharply contrasting strategies among the major contenders for the 1988 Republican nomination, but one fact stands out: The two leading candidates, Bush and Dole -- who together share about 65 percent of public support in opinion polls -- capture little if any of the revolutionary fervor and spirit of the early Reagan campaigns.

Tarrance's recognition of a dominant "establishment conservatism" is shared by many GOP strategists, but not all. Kemp, for example, is seeking in his stump speech to evoke a resurgence of a powerful anti-status quo conservatism: "I may not be the candidate of the Republican establishment or the status quo," he declares, "but I will be the candidate of boundless and equal opportunity for all Americans. I want to see the Republican Party be the leading party of human rights, civil rights, legal rights and equal rights for all."

The Rev. Pat Robertson's campaign also seeks to keep the Republican revolutionary spirit intact through a drive to mobilize evangelical, Christian outsiders into a crusading army determined to wrest control of the GOP away from the party regulars.

At the opposite end of the GOP continuum, Bush described his notion of the correct approach to the Republican voter of 1988 when he declared in his Houston announcement speech: "We don't need radical new directions -- we need strong and steady leadership. We don't need to remake society -- we just need to remember who we are." "You don't get 'new vision' candidates every four years," Robert Teeter, Bush's pollster argued, "What people want to see now is someone who can reinforce, refine, and build on what Reagan did."

While the Bush campaign is prepared to gamble that Republican voters -- and general election voters next November -- are willing to settle for a candidate who promises to consolidate Reagan's achievements, not to innovate himself, there is no such unanimity on strategy within the Dole camp. Dole himself has clearly rejected in substance and theory Reagan administration's policies that have led to a national debt of $2.4 trillion.

Dole is the only GOP candidate willing to consider tax hikes as part of a deficit-reduction package. "The American people are ready for bitter medicine," he declared two weeks ago, sounding the economic themes of his own postWar Kansas Republican roots. "We will either sacrifice for our children or we will continue to make our children sacrifice for us."

That sounds like the traditional green-eyeshaded-accountant austerity that the GOP consciously sought to eliminate from its image 10 years ago. And it was, in fact, Dole's newly chosen ten years ago. new campaign manager, William Brock who led the Republican National Committee in 1978 when it endorsed the Kemp-Roth tax cut in a move calculated to reshape the GOP into a party of optimism offering lower taxes, not sacrifice.

Brock tries to reconcile this apparent contradiction by saying that he believes Dole's current involvement in the drive to reduce the deficit will permit him to shift the emphasis of his campaign from austerity toward the argument that lowering the deficit will permit future economic growth and prosperity. He's betting that Congress will enact a Dole-backed package which is then seen by the public as restoring stability and growth to the market place -- a major set of "ifs" on which to base a political gamble.

Another Dole strategist, David Keene, contended that the electorate holds split views on the issues of the deficit and taxation: "The average Republican voter is the average conservative and they have been concerned about both of those things, the deficit and overtaxing. What you've got are candidates twanging different strings on that heart, but both of those strings are on the heart."

Teeter, Bush's pollster, disputes this assessment. "I don't see any evidence that there is a willingness to have any kind of tax increase . . . . That's a product of Reagan." Bush has staked out relatively moderate stands on arms control, chemical weapons and education, but he has adopted a firmly anti-tax posture: "I am not going to raise your taxes -- period."

While the stock market crash and its volatile aftermath have yet to reverberate into the economy in ways felt by the average voter, they have intensified doubts about the supply-side theories that led to the explosion of red ink during the Reagan administration. Most observers believe these doubts will reinforce the strength of more traditional, establishment-oriented candidates competing for the Republican nomination, i.e., Bush and Dole. "When people get nervous, they don't look toward someone who is going to revive the revolution," a dispirited Kemp supporter said.

The economic setbacks to new right economic theory come at a time when the conservative movement that flowered in the late 1970s and early 1980s has been severely weakened. This decline is most apparent in financial terms: Fund-raising by the network of conservative PACs organized in the late 1970s has nose-dived. The National Conservative Political Action Committee (NCPAC) has been torn by internal conflict after the death of its longtime leader, John (Terry) Dolan, and a series of lawsuits and countersuits has characterized the hostile relationship between many of the PACs, their fund-raisers and vendors.

At NCPAC, revenues for the first six months of this year have fallen to $1.1 million, compared to $3 million in 1985 and $2.6 million in 1983. The cash flow to the Fund for a Conservative Majority has fallen from $782,000 in the first half of 1985 and $822,000 in the first six months of 1983, to $418,000 from January through June this year.

The decline of the new right and the movement toward an establishment conservatism that places relatively low priority on such social issues as abortion may encourage the healing of some internal party wounds. But this trend also threatens the party's ability to continue to attract the working and lower-middle class voters who provided much of the new blood to the Reagan majorities in 1980 and 1984. These voters, who make up roughly a third of the GOP coalition in the general election, according to pollsters, have developed only weak ties to the Republican Party itself.

The splintering of anti-establishment conservative voters between Kemp and Robertson is likely to prevent a coalescing of these marginal Republicans behind either of the hard-right candidates. Instead the conflict may discourage these voters from participating in Republican primaries altogether, lessening the ability of the GOP, and either of its two most likely centrist nominees, Bush and Dole, to maintain the allegiance of such voters in the general election. The old conservative-moderate split in the GOP may be gone, but the ability of the party to attract a stable majority of the electorate has still to be tested.

Thomas Edsall covers politics for The Washington Post.