Anyone who follows national elections knows that there are two very different ways of interviewing a presidential hopeful. One way, exemplified by Kennedy School professor Marvin Kalb, is to involve the candidate in a substantial discussion of his future policy, the ways he reasons around an issue. The other, more provocative approach is to hurl incessant tough questions and see whether a potential leader can stand the heat.

"Candidates '88" was Kalb's attempt to present his style to Americans through one-hour interviews. And in his interviews, it is fair to say that viewers got true League of Women Voters material.

"It was very difficult for the American people to get a handle on each one of these candidates," says Kalb. "I thought it would be helpful...to see each one of the candidates in a serious setting...being asked serious questions."

Despite having interviewed all but one of the presidential aspirants, Kalb insists that he is no political pundit, preferring to cast himself in more objective roles. "For 37 years I was a reporter, and I'm now a professor...nothing sexy there," he states simply, as if his PBS shows were just another lecture series.

It is true that Kalb, a former CBS and NBC diplomatic correspondent, has found a less visible role for himself at Harvard--indeed, his arrival at the Kennedy School last year coincided with his removal from Who's Who in America. Despite this fall from grace, Kalb has established himself as an oft-quoted and--pundit or not--an influential figure in the campaign which reaches Massachusetts tomorrow.

In addition to his post as Murrow Professor of Press and Public Policy, Kalb heads the K-School's fledgling Shorenstein-Barone Center for Press, Politics, and Public Policy. It was through the center that he launched "Candidates '88," featuring 12 of the 13 presidential hopefuls for rounds of serious questioning.

Serious questions, however, are no guarantee of serious answers. And even an unprecedented full-hour format does not ensure that candidates will deal with the issues, and not launch into tired campaign rhetoric. Kalb concedes that Sen. Al Gore Jr. '69 (D-Tenn.), for one, used the show more to present his image than to discuss policy. "Each one of them came up here to look the best he could, to sound the best he could," says Kalb. "A politician running for the presidency who did not take advantage of an hour of free time would be a fool."

Even faced with this dilemma, this tendency towards soapbox sermonizing, Kalb's tendency is not to press harder, or put a candidate on the spot. This is largely due to the way he views his role as interviewer. The K-School professor is perhaps one of the last journalists to follow the example of Edward R. Murrow himself, emphasizing straightforward questioning while avoiding less friendly, if sometimes more effective, tactics.

"I never intended to trip anyone up," says Kalb. "I don't want to do that, it's not my style...I don't think you get information out when you try to trip up a candidate." He says his show "never was conceived of as an opportunity for me to engage in self-promoting, hyperbolic questions designed for the viewer to say "Wow, isn't Marvin smart.' " Kalb insists on deriding such hostile cross-examination as a diversion from any serious discussion of political issues.

While Kalb exemplifies the laid-back, more intellectual approach, the more provocative method can be found in David Frost's program "The Next President." Frost, who also interviewed a dozen would-be presidents in hour-long installments, made every effort to catch his guests off guard. Frost asked the Rev. Pat Robertson to explain what it was like to speak in tongues, and relentlessly questioned Rep. Jack Kemp (R-N.Y.) about contradictions in his views on abortion.

Kalb, who says he saw three of Frost's interviews, balks at the slightest comparison between the two shows. "I don't think there was anything similar at all except that they were both within an hour context and they were both on television," he says. "If [the three I saw] were representative of the other nine, they were soft, People magazine, substanceless fluff," says Kalb. Moreover, Kalb points out that despite Frost's higher budget and more explosive style, "Candidates '88" received more coverage in the media. Clearly, even an academic likes to keep track of his headlines.

Despite the candidates' inevitable image flaunting, Kalb says that, based on his expectation, he was impressed by many of those who appeared on his show. He cites the Rev. Jesse Jackson's "growth as a political figure" and Gov. Michael Dukakis' "intellectual capacity." Kalb also extends praise to Pete DuPont, now out of the race, and Rep. Richard Gephardt (D.Mo.).

On the other hand, Kalb says he was "disappointed" with Al Haig's interview. "I know he is much smarter than he came through," says Kalb, "and I was surprised that he did not take better advantage of the occasion than he did." He expresses similar disappointment with Sen. Paul Simon (D-Ill.) for "his overly simplistic presentation of very complicated ideas, particularly the manner in which he said he was going to balance the budget in three years."

What of the one candidate who chose not to appear on "Candidates '88"--Vice-President George Bush? "Well, it gave us a lot of free publicity," Kalb says matter-of-factly. Bush's decision also opened up a spot on the show--which was conveniently filled by former Colorado Sen. Gary Hart after his reemergence in the campaign. Kalb calls such a programming break "pure serendipity."

Super Tuesday provides an excellent case study for the Shorenstein-Barone Center, an interesting test of how a media strategy can boost candidates' chances and influence a campaign. Tomorrow's election will be the first major presidential contest since the center was established.