Because of erroneous information from the Maryland Republican Party, the year that U.S. Senate candidate Thomas L. Blair headed a Republican fund-raising organization was reported incorrectly yesterday. Blair headed the Maryland Republican Eagles since last summer. (Published 1/21/88)

Thomas L. Blair, the leading Republican candidate to challenge Sen. Paul S. Sarbanes (D-Md.), was purged from the voter registration rolls two years ago for failure to vote in the preceding five years, according to Montgomery County Board of Elections records.

Blair, 43, a businessman from Potomac, renewed his registration as a Republican on Dec. 24, 1987, four days before he filed as a candidate in the March 8 Republican primary for the U.S. Senate. A state election official in Annapolis said that a candidate must be a registered party member to run for office in that party's primary.

Election records showed that Blair last voted in the general election of 1980.

Blair, like the eight other Republican candidates in the upcoming primary, is a relative political unknown. Yet, he is viewed as one of the best hopes of Maryland's beleaguered Republican Party because of what party leaders say is his promise to spend substantial amounts of his own money in a race against the solidly supported and well-financed Sarbanes.

Blair, founder of a Rockville health care company that he sold in 1986 for $35 million, refused yesterday to talk to a reporter. Richard Hines, a vice president in Jurgovan & Blair, the health maintenance organization consulting firm that Blair still helps run, said that Blair made "a policy decision" not to speak with the press until he makes his formal announcement, expected in February.

Hines said he relayed questions about Blair's voting record to him. According to Hines, Blair doesn't feel that his voting record is "of much importance" and "he doesn't want to make a big deal of it," Hines said.

According to Hines, Blair thought he had voted in 1984 and if the record shows he didn't, it was probably because he was out of town on business. This was a time, Hines said, when Blair was building the business and working to support his family.

Hines said that Blair said he has voted in every other presidential election. A registrar at the county Board of Elections said no record could be found of Blair's voting prior to 1980, but that the information might be contained in archives.

The county records showed that Blair registered as a Republican on June 17, 1980, and voted once that year, in the general election. He was removed from the rolls from January 1986 until he reregistered last month.

State Republican officials said they knew of Blair's voting background but that they did not see it as any kind of issue. Nelson Warfield, executive director of the state GOP, praised Blair, citing his work since 1986 as head of the Maryland Republican Eagles, whose members each contributed $2,500 for the state Republican party.

Republican National Committee member Richard P. Taylor said he was among those who had encouraged Blair, as well as other young Republicans, to run. He said that voting is certainly important but that he is not sure Blair's individual voting record is "all that big a deal." Blair is a lifelong Republican, who thinks like a Republican and would, if elected, "effectively represent the people," Taylor said.

Taylor suggested that it is "nitpicking" to focus on his voting history and cited what he called the press' obsession with "every little thing." "Take a look at the forest -- the whole candidate; instead of the trees," Taylor said.

Blair's biggest challenge in the primary had been from Noel C. Koch, also of Potomac and once the Defense Department's chief expert on counterterrorism, who dropped out of the race, saying he thinks Sarbanes is unbeatable.

Another candidate seen as ahead of the pack is Patrick L. McDonough of Baltimore, a former member of the Maryland House of Delegates who was elected as a Democrat in 1978 and defeated for reelection four years later. McDonough switched his party affiliation to Republican in October 1987, according to the Baltimore City Board of Elections.

He is not the only candidate to have switched parties. Albert Ceccone of Chevy Chase, who lost last year's Republican primary for county executive, registered as a Democrat in September 1972 and switched parties in May 1973, the Montgomery Board of Elections reported.

Two candidates have gone back and forth in their party affiliations. James Gordon Bennett of Silver Spring changed party affiliations four times between 1966, when he registered as a Democrat, and 1986, when he changed back to a Republican. Monroe Cornish of Baltimore switched six times between 1955, when he registered as a Democrat, and 1987, when he registered as a Republican.

Staff writer Robert Barnes contributed to this report.