Virginia Republicans who last month nominated Richard D. Obenshain as their Senate candidate consider themselves conservative. But they overwhelmingly believe Obenshain is even more conservative, according to a survey by three College of William and Mary government professors.

The survey appears to underscore what may be a fundamental campaign probably for the GOP nominee: persuading Virginia voters that his views are not too far to the right of their own.

Obenshain already has been accused of being an "extremist" by his Democratic opponent, Andrew P. Miller, a former state attorney general. Miller has said he will attempt to make Obershain's conservatism a major issue in the fall campaign.

An election day survey by The Washington Post last year showed that the Virginia electorate views itself as somewhat conservative, but still close to the political middle. In the 1977 elections for governor, lieutenant governor and attorney general, voters chose the candidates that they considered closest to their moderate-conservative viewpoint and defeated the most conservative and most liberal candidates in the field.

Responses to questionnaires answered by 1 out of every 16 of the 7,300 GOP delegates to the Republican convention showed that almost 8 out of 10 viewed themselves as "somewhat conservative" to "very conservative," but more than 9 out of 10 put Obenshain in that most conservative category.

Significantly, the conservative GOP convention and the much more liberal Democratic convention delegates, also surveyed by the William and Mary professors, had sharply differing views of Miller but almost identical views on Obenshain's political outlook.

More than 8 of 10 Democratic delegates who answered the questionnaires at their convention put Obenshain in the "somewhat" to "very conservative" range. Exactly the same portion of Democratic and Rebeled Obenshain "very conservative."

Seven out of 10 Republican delegates said they viewed Miller as Democratic voncention, 7 out of 10 responding to questions somewhat to very liberal but at the [TEXT OMITTED FROM SOURCE]

One of the most striking results of the Democratic convention survey was the finding that unsuccessful Senate candidate G. Conoly Phillips, a born-again Christian and Norfolk city concil member, brought a significant number of Republicans to the Democratic nominating session. (One out of seven of the 2,798 Democratic delegates responded to the survey.)

Phillips ran third in the convention balloting and two out of five of his supporters surveyed identified themselves as strong Republicans or independents leaning toward the Republican Party. Thus, the survey indicated that one of every 16 Democratic convention delegates actually was a Republican or Republican leaner.

This is the same percentage of Republican participation that a Washington Post survey revealed in the Democratic primary for governorin 1977.

switched from a primary to a convention this year, one of the advantages cited by party officials was the elimination of Republican participation in their nominating process. The Phillips candidacy, according to the survey.

Ironically, when the Democrats

Obenshain was decisively favored by party regulars who have attended past conventions, according to the survey, Republican delegates were evenly divided in their opinion of which of their three leading candidates - Obenshain, former Navy secretary John Warner and former Gov. Linwood Holton - would be the strongest candidate in the general election. The Democratic delegates considered Miller their strongest candidate by an overwhelming margin.

The convention surveys drew sharp contrasts on major national issues between the Republican and Democratic delegates, but otherwise, the delegate profiles of the two conventions were strikingly similar. The ages, incomes and educational levels of the two groups were almost identical. The incomes and educational levels of both were decidedly higher than those in the general population.

The surveys were conducted by professors Alan Abramowitz, John McGlennon and Ronald Rappaport. The questionnaires they distributed were answered by 480 Democratic delegates and 485 Republicans.