When Marion G. (Pat) Robertson formally announced he was running for president a month ago, he resigned his ministry and his ties to the Christian Broadcasting Network (CBN), saying he wanted to assure the public he believed in the total separation of church and state.

But a review of Robertson's activities over the past 2 1/2 years -- based on public and private documents and interviews with current and past CBN and campaign officials -- presents a different image. It provides a detailed record of how the minister used the religious empire he created to carefully lay the groundwork for his run for the White House.

Robertson's blurring of the lines between his charitable activities and his political ambitions has given him a major advantage over other candidates, who did not control the tax-exempt assets of a multimillion-dollar corporation.

The Internal Revenue Service is investigating whether the relationship between CBN and Robertson's political activities violated the prohibition against using charitable dollars in politics.

The record shows that, while president of CBN and before declaring as a candidate, Robertson:

Recruited a longtime associate in early 1985 to establish a direct-mail computer operation with the aid of seed money from a CBN affiliate. George F. Border set up the company with the idea it might become the base for Robertson's presidential fund-raising efforts a year later.

Used the tax-exempt Freedom Council -- funded by millions of dollars from CBN -- to help elect his supporters in Michigan's GOP convention delegate-selection process.

Robertson maintained he was not a candidate at the time and that he and the council were simply getting Christians of both parties involved in politics. But after key Michigan votes in June and August 1986, Robertson wrote supporters of the Freedom Council that "the Christians have won" and wrote CBN employes, "This was a smashing triumph on our part and a humiliating defeat for the vice president {George Bush}."

Authorized, beginning in 1985, the rental of parts of CBN's one million-name donor list for use by the Freedom Council, a separate political action committee, and his campaign committee. The rental of the entire list to a campaign contractor, over the protests of some CBN executives, was the key to building the donor base he used to raise more than $11 million in 14 months, more than any candidate but Bush.

Benefited politically from the help of major supporters of his causes. This included a glowing account of his presidential stature in The Saturday Evening Post in early 1985, written by the magazine's owner, a financial supporter of Robertson's. Reprints of the story were circulated and Robertson referred to the article in letters to CBN and campaign donors last year as a sign of the groundswell of support for his candidacy.

Used the CBN twin-engine passenger jet, purchased from country singer Kenny Rogers, for travels to numerous key campaign states starting last year. A former Secret Service agent with experience on presidential candidate protection details was hired by CBN as director of security about the same time and often accompanied Robertson on his trips.

Had access to CBN-financed surveys of the well-known Republican polling firm of Lance Tarrance on the electability of Christian leaders. Tarrance later severed the connection, fearful it conflicted with the interests of another client, Rep. Jack Kemp (R-N.Y.), one of Robertson's GOP competitors.

Received credit in a campaign press release for directing $25,000 in CBN funds last year to the governor of Iowa to help needy farmers in the state, site of a key early presidential test. A CBN project also sent more than $200,000 in cash and goods to Iowa farmers, more than twice what it sent to five neighboring states with similar farm problems.

Norman Berman, who was vice president for fund raising at CBN until July, said in an interview that executives at the network "did express inevitable concerns" about whether some of Robertson's activities amounted to partisan politics and thus might jeopardize CBN's tax-exempt status. "It was difficult to understand why some things were happening," he said. "But we didn't always know the facts."

Berman said he was assured personally by CBN attorney Randy Morell that the rental of the CBN mailing list to a campaign contractor -- which Berman opposed -- was legitimate because the network charged a premium. Berman said Robertson personally worked with him in setting the price, about three times the industry top for list rental.

The contractor, Victory Communications of Arizona, paid about $600,000 for two uses of the list, another knowledgeable official said. The campaign committee, Americans for Robertson, also paid CBN for the use of the plane and for the expenses of network security personnel.

Larry Batdorf, an IRS spokesman, would not comment on the specifics involving CBN and Robertson and said there are no published rulings on the issue. "However," he added, "we feel that an excessive payment or a higher than normal rental fee would be only one factor in determining whether there's been an arms-length transaction, and it would not be an overriding factor."

Other factors would include whether the overall purpose of renting or selling an asset was to raise funds for charitable purposes and whether such assets are available to others among the general public, he said. The principle would apply to the use of other assets of a tax-exempt organization, such as a plane, polls or security guards, he added.

G. Benton Miller Jr., a spokesman for CBN, declined to answer any questions last week about the network's dealings with the Robertson campaign. "Since it has been reported that the IRS is currently auditing us, upon advice of our legal counsel and our independent auditor, we are not prepared to make any further statements concerning CBN's proprietary financial information," he said.

The Robertson campaign declined to respond to numerous phone calls seeking comment on Robertson's use of CBN assets for activities with political overtones.

Robertson also stretched federal election laws in the period before he formally declared his candidacy, especially with his expansive definition of what constitutes "testing the waters." That is the phase of a campaign that does not require financial disclosure.

His activities in the preannouncement period included raising funds for television ads in South Carolina, and making direct-mail appeals aimed at getting supporters involved in the Florida Republican straw poll and primary, activities usually considered those of a candidate.

In addition, there are signs that the Robertson campaign might have violated federal election laws in accepting $337,500 on Sept. 30 from a shell corporation set up by a campaign aide in Denver. The money was a deposit on the purchase of the campaign's computer system.

The Washington Post reported that records indicated the Denver firm, which isn't registered to do business in Colorado, paid more than $100,000 above the sum that the computer system had cost the campaign nine months earlier.

Robertson aides said the price was not inflated because the campaign had bought other computer-related equipment since then "to augment" the system. Robertson told a Boston radio interviewer he had a letter from IBM showing the campaign actually sold the system "for $15,000 less than it was worth."

A review of more than 1,100 pages of campaign expenditures could uncover only $13,000 in purchases of additional computer-related equipment. The campaign did not respond to repeated requests for release of the IBM letter, the source of the $337,500 payment, and identification of the $87,000 worth of augmented equipment that does not appear to be in the campaign spending report as required.

As far back as 1979, magazine articles have mentioned the possibility that Robertson was interested in running for president. But several Robertson intimates point to the laudatory Saturday Evening Post cover story in March 1985 as a real kickoff for the campaign.

The story -- "CBN's Pat Robertson: White House Next?" -- was written by Cory SerVaas, a Robertson supporter from Indianapolis who heads the nonprofit group that now publishes the magazine. SerVaas, a member of President Reagan's commission on AIDS, has made regular appearances on a health show on CBN. She could not be reached for comment.

Robertson has referred to the article in messages to his CBN donors and to political supporters.

Shortly after the article appeared, two more important pieces of a potential presidential campaign were put into place. Robertson coaxed Border, a former CBN vice president, out of retirement in Florida and urged him to return to Virginia Beach to set up a computerized direct-mail business and a political action committee.

In June 1985, the PAC, called the Committee for Freedom, was set up with Border as the treasurer. On July 1, Border incorporated his new firm, G.B. Computer Services Inc., and later that year he bought nearly $600,000 in computer gear, including a large IBM computer, software and equipment to be used for direct mail.

The idea, according to people familiar with the agreement, was that Border received an exclusive contract -- at cost plus 10 percent -- to handle administrative details, from insurance benefits to phone service, as well as to raise funds for four Robertson-affiliated groups. At the proper time, he would then be in position to take over fund raising for a presidential campaign.

Border said in an interview that he and Robertson had discussed the possibility of presidential campaign work for his company, but that Robertson never promised that his firm would be hired.

Asked if Robertson or any of his groups provided any of the down-payment money he used to buy the computer system, Border said, "not directly." A person familiar with the transaction said the Freedom Council -- which was heavily funded by CBN -- advanced funds to Border to use as part of the down payment.

That same summer of 1985, CBN hired Tarrance's Houston polling firm to do a $30,000 survey for the Freedom Council -- which Robertson had founded four years earlier to get Christians active in politics -- and an affiliated think tank, the National Perspectives Institute.

Among its objectives, the survey sought to determine the likelihood of the American electorate accepting and voting for candidates who have a strong Christian heritage and evidence of Christian commitment. The survey found that the public was more prepared to vote for a Christian businessman than a preacher or a Christian television personality.

A few months later, the Tarrance firm turned down a request that it do more polling on the question of Robertson's name recognition. Tarrance, who polls for Kemp, said in an interview that he declined because he felt "they were trying to move me into a position where it would appear I was Pat Robertson's pollster . . . and I thought that was a potential conflict."

CBN then turned back to the George Gallup organization, which for years has included in its surveys questions about the recognizability of Robertson and CBN's featured show, "The 700 Club."

It was also in the fall of 1985 that the Freedom Council began increasing the size of its professional staff and receiving massive infusions of money from CBN. {In the one-year period before April 1986, the council and an affiliate collected $4.6 million from CBN, according to the network's federal tax return.}

Much of that money went into political activity in Michigan and is a subject of the IRS audit.

In the same period, the five-member board of CBN -- which included Robertson and his wife Adelia -- took an unusual step. For the first time, it rented part of the mailing list of faithful donors who were contributing about $150 million to tax-exempt CBN. It rented the list to Border for use in raising funds for the Robertson PAC, according to Berman, who was head of fund-raising at CBN at the time.

In the spring of 1986, Berman said, part of the list, about 17,000 names of major donors, was rented again to the PAC, through the Border firm. About the same time, another part of the CBN donor list -- more than 40,000 contributors in Michigan -- was rented to the Freedom Council, through another middleman, Michael Clifford, whose firm, Victory Communications, was putting on a teleconference in Detroit in May, with Robertson as the featured speaker.

The biggest rental was in July 1986, when the main 970,000-name CBN list was rented to Victory for two mailings, sending out invitations and later soliciting political donations keyed to a televised Robertson appearance at Constitution Hall here on Sept. 17.

As part of that rental, Berman recalled, the Clifford firm was allowed to use parts of the list to invite CBN donors living near two other fund-raising sites -- Nelson Bunker Hunt's ranch near Dallas on Aug 1. and the Anaheim Convention Center the next day.

"I opposed renting the list, both philosophically and parochially, because I was trying to protect our fund-raising tool," Berman said.

In the meantime, both the PAC and the Freedom Council were becoming more active. The council's income had jumped to nearly $5 million in 1985, much of it from CBN.

Federal Election Commission records for the Committee for Freedom show large payments to R. Marc Nuttle, now Robertson's campaign manager, from January through August of last year. He or his Oklahoma firm was paid more than $150,000 in legal and consulting fees and expenses.

Clifford's Victory Communications also shows up on the PAC payroll for the spring of 1986. Both Nuttle and Clifford -- who is now media adviser to defrocked PTL evangelist Jim Bakker -- were consultants to the Freedom Council as well.

CBN itself was suffering from a decline in revenues and was forced to make layoffs and cut its budget $25 million in spring 1986, and some network officials wanted to cut its donations to the Freedom Council. The council moved to attract other donors by getting its tax status changed to tax-deductible.

In May of last year, the Freedom Council hired Clifford's firm, with the aid of CBN's Michigan donor list, to sponsor the Robertson rally in Detroit. The council also sponsored a joint dinner with the PAC in Washington that month, hoping to attract $25,000 donations -- $5,000 to the PAC, the legal limit, and $20,000 to the Freedom Council.

The PAC also payed CBN for the use of its jet on occasion, starting in June.

July was an especially active month for the Robertson forces. A state version of the PAC was set up in Michigan and spent money in the precinct selection process that the Freedom Council was focusing on, according to its reports in Lansing.

Two former top Freedom Council officials set up separate, independent committees to "draft" Robertson that month. And Robertson announced he was authorizing formation of Americans for Robertson as an exploratory presidential committee. Among its first acts was hiring Clifford, who with the aid of the CBN donor list, would organize the Sept. 17 event.

Robertson announced that night, in a speech beamed to more than 200 locations around the country by satellite, that he would run if he could collect the signatures of 3 million supporters.

He and his aides said at the time that the national appeal for petitions was just that, a call for support. A year later it became clear that the massive effort was also something else: smart politics.

The names on those petitions have been mined over and over, in direct-mail fund-raising efforts, and in state campaign efforts to recruit volunteers and voters.

Special correspondent Susan Kelleher in Denver contributed to this report.