CHESAPEAKE, VA. -- Television evangelist Pat Robertson, using a tax-exempt and supposedly nonpartisan "citizen action" organization, has raised more than $13 million for an ambitious and largely unheralded foray into electoral politics aimed at electing "pro-family Christians" to Congress and achieving "working" control of the Republican Party by the 1996 election.

Since it was founded in 1989, Robertson's Christian Coalition has in many ways eclipsed the impact of the defunct Moral Majority, tapping state and local affiliates to achieve majorities or near majorities on Republican central committees in more than a half-dozen states and by placing 300 members as delegates to last month's Republican National Convention.

Now Robertson, an unsuccessful GOP presidential candidate in 1988, is planning a massive, get-out-the-vote effort for this year's November elections, including "in-pew" registration at churches, the distribution of up to 40 million "voter guides" on "family" issues and the use of computer- assisted telephone banks to help elect favored candidates in key races.

"I think this will be the most effective coordinated activity by evangelical Christians that we've ever seen," Ralph Reed Jr., executive director of the Christian Coalition, said of the group's electoral activities. "I don't want to belittle Jerry Falwell or the Moral Majority. But the Christian Coalition as a model represents a more mature, more developed and more politically sophisticated vehicle for Christian political activism."

The group -- which claims 250,000 members in 49 states -- also is aggressively backing initiatives against gay rights in Oregon and Colorado and working to defeat a proposed equal rights amendment in Iowa that Robertson wrote in a recent fund-raising letter would advance "a feminist agenda . . . that encourages women to leave their husbands, kill their children, practice witchcraft, destroy capitalism, and become lesbians."

Some GOP strategists, while privately embarrassed by some of Robertson's language, acknowledge his activities may be decisive in bringing out Republican voters in some southern and border states, a political calculus underscored by President Bush's plans to speak here Friday night before 1,100 Christian Coalition activists expected to attend the group's second annual "Road to Victory" conference.

Critics of the organization, however, contend that at least some of the Christian Coalition's activities have become so openly partisan that they violate Internal Revenue Service rules. In addition, Robertson's increasingly hard-line rhetoric on abortion, gay rights and other social issues has alarmed moderate Republicans who fear his aggressive agenda is turning off voters and threatening the future of the party.

"What they're doing along the way is antagonizing the hell out of mainstream Republicans who have just gotten fed up," said John Treen, the Republican Party chairman in Jefferson Parish, La., who estimated that more than half of the party's central committee in Louisiana is now in the hands of Christian Coalition members. "They're using the Republican Party as the pulpit for their religious views."

The coalition was incorporated as a nonprofit 501C(4) group under the tax code, which grants tax-exempt status to charitable, educational or social welfare groups as long as they do not engage in partisan politics as their "primary" activity. Reed said in interviews that the group has fulfilled this requirement because it is an "issues organization" whose actions are generally aimed at influencing "the public policy process" without regard to party affiliation.

But tax records and Christian Coalition documents show extensive financial and political ties to national and local Republican Party organizations, connnections that are being reviewed by IRS auditors.

While most of the Christian Coalition's money comes from direct-mail fund-raising, for example, records here show that the largest single contributor has been the National Republican Senatorial Committee, which gave $64,000 -- described by Reed as "seed money" -- in October 1990.

Records also show the Christian Coalition in turn has made $31,000 in political contributions, including $25,000 for what Reed called "generic party-building" to a local Virginia Republican Party committee during last year's state legislative races. Those races were openly targeted by the Christian Coalition, whose members distributed thousands of pro-family voter guides that were heavily tilted on behalf of local Republican candidates, a key factor, many Democrats said, in the GOP picking up eight seats in the Virginia Senate.

"They openly targeted me by using their phone banks starting in July 1991 and getting their voters to the polls, calling them as many as five times," said Moody E. Stallings Jr., a Democratic state senator form Virginia Beach who lost to a Christian Coalition-backed Republican. "I would have to say they were a major factor in my defeat."

Robertson trumpeted the results of the Virginia state legislative races in a fund-raising letter on Christian Coalition stationery two months ago, noting the "stunning upset victory" of his forces in legislative elections in his home base of Virginia Beach. "This was the first time that a Republican majority had been elected from this city in over 100 years!" Robertson wrote.

"America is at a crossroads," Robertson said in the same letter. "Either she returns to her Christian roots . . . or she will continue to legalize sodomy, slaughter innocent babies, destroy the minds of her children, squander her resources and sink into oblivion."

But even more important than its electoral efforts, some critics said, has been the Christian Coalition's thinly disguised grass-roots attempts to win control of local, state and ultimately the national Republican parties. At last year's "Road to Victory" conference, for example, Christian Coalition officials passed out manuals on the Republican delegate selection process, complete with state-by-state run-downs on party caucuses and conventions.

"We want . . . as soon as possible to see a working majority of the Republican Party in the hands of pro-family Christians by 1996," Robertson told delegates to the conference.

Robertson's supporters have followed that agenda, pouring out in extraordinary numbers at local caucuses and other party meetings to elect state GOP committee members and national convention delegates, party officials said. Treen said that in last spring's party caucuses in Louisiana, as many as 200 Christian Coalition members attended some sessions, enabling the group to capture a majority of the state's delegates to the Houston national convention.

"Their only purpose for existence as far as we've been able to determine is to take over the Republican Party from the bottom on up," said Robert Boston, a spokesman for the Americans United for Separation of Church and State, a frequent critic of Robertson and the Christian Coalition. "They're running the Republican Party in certain parts of the country, and they're doing it all with a tax-exempt status, and the IRS so far has done nothing."

This is not the first time that legal questions have been raised about Robertson's political activities. In the middle of his 1988 GOP presidential race, the IRS launched an investigation into allegations by former employees that Robertson illegally used millions of dollars from his tax-exempt television network, the Christian Broadcasting Network (CBN), and a now-defunct political organization called the Freedom Council, to finance his campaign. The results of that audit have never been publicly disclosed and Robertson officials declined to discuss them this week.

Reed acknowledged in an interview that the IRS is conducting a separate audit of the Christian Coalition and that the agency has yet to approve its 1989 application for 501C(4) tax-exempt status. Marcus Owens, director of exemption organizations for the IRS, said the lack of a formal ruling means that the organization can continue to raise and spend money but may be liable for back taxes if the IRS determines that it did not qualify for the exemption.

Owens declined to discuss the specific activities of the Christian Coalition, but noted that a 501C(4) organization has considerably more latitude to engage in nonpartisan "educational" political activities -- such as distributing voter guides -- than a 501C(3) charity, such as Robertson's CBN. Another difference is that people who donate to a 501C(3) can deduct their contributions on their taxes but cannot for donations to a 501C(4) organization, such as the Christian Coalition.

Nevertheless, Owens said, financing political party organizations or involvement in internal political party politics would not qualify under the IRS's standards for either category.

"Certainly we would feel that providing money to a particular party is equivalent to providing it to a candidate," Owens said. "In our view, political party activities are clearly campaign intervention activity only slightly removed from the campaign."