ANNAPOLIS, DEC. 28 -- The Maryland Republican Party is long on people willing to challenge U.S. Sen. Paul A. Sarbanes (D-Md.), but on the final day to register for next year's congressional elections, it was short on names Maryland voters have heard before.

The deadline today brought no unwelcome surprises for Sarbanes, who is in a strong position to win his third term. He is raising a significant war chest, has a strong Baltimore base and no serious opposition to become the standard bearer of the state's dominant political party. And although Republicans criticize Sarbanes for being invisible, he enjoys solid support in the polls.

Ten Republicans paid the $290 qualifying fee to give it a try anyway. But the list for the March 8 primary doesn't include names such as former U.N. ambassador Jeane Kirkpatrick or Maryland racing magnate Frank De Francis or even former Baltimore Colts great Johnny Unitas, all of whom were courted by Republicans searching for a big name to head the state ticket.

Instead, the list features Noel C. Koch and Thomas L. Blair, both of Potomac, and Patrick L. McDonough of Baltimore -- and those are the three whom party leaders identify as being at the head of the pack.

"Really, the sad commentary is that Maryland doesn't have a viable two-party system," said De Francis, who said he made a final decision Christmas Eve not to seek the nomination. "The lack of candidates is a sad commentary on our failure" to build the party, he said.

Other Republicans naturally don't think the situation is that dire, although state GOP Chairman Daniel Fleming said the party is in a "transition period" in which few of the Republicans elected on the local level are ready to make the jump to higher office.

But others worry that the party once again is heading into a statewide election without a candidate well-known to Marylanders. A similar situation in 1986 led to overwhelming victories by Democrat Gov. William Donald Schaefer and U.S. Sen. Barbara A. Mikulski.

Even some of those who registered to run aren't sure whether chances for an upset of Sarbanes are good. Koch, a former Pentagon official who had a role in the Iran-contra affair, said he still hadn't made a final decision on whether to wage a campaign.

Koch figures it will take at least $2.5 million to be competitive against Sarbanes, and will decide within three weeks whether it is possible to raise that much money. "But the real question is whether he {Sarbanes} is really vulnerable," Koch said.

Sarbanes is trying his best to look formidable. He has raised more than $600,000, which is better than he has done at this point in either of his previous races, he said. He is challenged within his own party by B. Emerson Sweatt of White Plains and A. Robert Kaufman of Baltimore, both of whom lost soundly in the 1986 Democratic primary for the Senate.

Republican National Committeeman Richard P. Taylor said he wasn't worried about the relative anonymity of the Republican candidates. "Name recognition is not a problem if your candidate is truly credible," said Taylor. "And in terms of qualifications of candidates, I don't think you can find two better than Noel Koch and Tom Blair."

Blair was the surprise entry in the race. A 43-year-old native of Prince George's County, Blair was cofounder of a Rockville health maintenance organization consulting firm that was sold last year for $35 million. Fleming said Blair told him he was "prepared to sink significant resources" into the race. Blair is head of the Maryland Eagles, whose members each contribute at least $2,500 a year for the state Republican Party.

Blair had quietly talked to party officials for months before registering for the race today. He refused to take questions today, saying through a spokesman that he had planned a formal announcement on Jan. 7.

Koch (pronounced cook) said Blair's entry into the campaign would have no effect on his ultimate decision. Koch said Blair was running because "he has nothing else to do," and that if Blair used too much of his own money on the race, it would become a campaign issue.

Koch is formerly the Defense Department's top counterterrorism official, who resigned in 1986 to set up his own private security consulting firm in Arlington. Koch testified before the Iran-contra hearings last summer that he had detailed knowledge of the arms deal to Iran because of his position in the Defense Department. Koch, 48, like Blair has never run for public office, but was recruited by the national party.

Koch and Blair are joined by McDonough. He is a former member of the Maryland House of Delegates who was elected as a Democrat in 1978 and defeated for reelection four years later. This is his first race as a Republican. The other Republican candidates who registered to run were Robert Zarwell of Severna Park; Monroe Cornish of Baltimore; John C. Webb Jr. of Gaithersburg; Albert Ceccone of Chevy Chase; James Gordon Bennett and Herbert Rosenberg, both of Silver Spring, and Horace Stuart Rich of Baltimore. Webb and Bennett lost races for the Maryland House in 1986. Ceccone lost the Republican primary for Montgomery County executive the same year.

Registration also closed for congressional races, with some freshmen luckier than others. Seven Democrats will vie for the chance to run against Republican Constance A. Morella for her Montgomery County seat. No current office holders decided to challenge freshman Democrat Tom McMillen for the seat he won in a photo-finish in 1986. And it appeared that first-term Rep. Kweisi Mfume, a Democrat from Baltimore, would be the only Maryland member of Congress to be reelected without opposition from either party.

The following candidates have filed for congressional races: 1st Congressional District (Most of the Eastern and Western Shore and southern Maryland)

Roy P. Dyson, Great Mills, Democrat (incumbent)

Morris Durham, Aberdeen, Democrat

Wayne Gilchrest, Kennedyville, Republican

John Vance Meyers, Sunderland, Republican

Karry Charles Williams, Stevensville, Republican

2nd Congressional District (Most of Baltimore County and part of Harford County)

Helen D. Bentley, Lutherville, Republican (incumbent)

Joseph Bartenfelder, Baltimore, Democrat

Mitchell Coleman, Baltimore, Democrat

Blaine Taylor, Baltimore, Democrat 3rd Congressional District (Part of Baltimore, part of Baltimore County and part of Howard County)

Benjamin L. Cardin, Baltimore, Democrat (incumbent)

Charles Walker, Baltimore, Democrat

Roy F. Carraher, Baltimore, Republican

Frederic Parker, Columbia, Republican

Ross Pierpont, Baltimore, Republican

Douglas Harris, Randallstown, Republican

4th Congressional District (Anne Arundel and part of Prince George's counties)

Tom McMillen, Crofton, Democrat (incumbent)

John Rea, Annapolis, Democrat

Edward Quirk Jr., Glen Burnie, Democrat

Claude Roxborough, Temple Hills, Republican

Partick Lucky Stevens, Edgewater, Republican

5th Congressional District (Most of Prince George's County)

Steny Hoyer, Berkshire, Democrat (incumbent)

John Eugene Sellner, Fort Washington, Republican

Gregory Washington, Forestville, Republican

6th Congressional District (Western Maryland, part of Montgomery and Howard counties, and Frederick and Carroll counties)

Beverly L. Byron, Frederick, Democrat (incumbent)

Anthony Patrick Puca, Potomac, Democrat

Kenneth Halsey, McHenry, Republican

7th Congressional District (Part of Baltimore)

Kweisi Mfume, Baltimore, Democrat (incumbent)

8th Congressional District (Most of Montgomery County)

Constance A. Morella, Bethesda, Republican (incumbent)

George Benns, Silver Spring, Democrat

Rosemary Glynn, Bethesda, Democrat

Michael Gudis, Burtonsville, Democrat

Peter Franchot, Takoma Park, Democrat

Allan Lichtman, Bethesda, Democrat

Ralph Shur, Germantown, Democrat

James Walker Jr., Bethesda, Democrat