A presidential race that is unusually competitive by Maryland standards is the main drawing card as the state's roughly 2.2 million registered voters prepare to go to the polls on Nov. 6.

With no state-wide offices on the ballot this year, and all but one of the state's eight incumbent members of the House of Representatives favored, the presidential contest and some scattered ballot referenda will provide most of the excitement on election night.

As one of six states that -- along with the District of Columbia -- voted for President Carter over Ronald Reagan in 1980, Maryland was as recently as a few months ago widely viewed as a mortal lock for Democratic candidate Walter Mondale. But Reagan's apparent strength nationwide has even trickled down to a state that has gone Republican in a presidential year just once since 1956. Despite a 3-to-1 voter registration margin in favor of the Democrats, Reagan has been running well ahead of his Democratic challenger in Maryland polls conducted since the summer conventions.

A strong Reagan showing could prove most beneficial to the Republican challenger in Maryland's second congressional district. There, in Baltimore and Harford counties, Helen Bentley has mounted a vigorous campaign to unseat U.S. Rep. Clarence Long, a 22-year Democratic veteran who has survived two previous Bentley challenges.

Closer to Washington, U.S. Rep. Michael D. Barnes is running for a fourth term in the eighth district, which includes about half of Montgomery County. He is opposed by Republican Albert Ceccone and Libertarian candidate Samuel K. Grove.

Rep. Steny Hoyer, who since 1981 has represented the fifth district, which includes most of Prince George's County, is running against Republican John Ritchie.

Maryland's only Republican member of the House, Marjorie S. Holt, is running for a sixth term from the fourth district, which includes all of Anne Arundel County and the southern portion of Prince George's. She is being challenged by Democrat Howard Greenebaum.

Sixth district Rep. Beverly B. Byron is running for a fourth term in the district that runs from Western Maryland to portions of Montgomery County. She is opposed by Republican Robin Ficker.

In the first district, which includes the eastern and western shores of the Chesapeake Bay, incumbent Democrat Royden P. Dyson is seeking a third term against Republican Harlan C. Williams.

And third district congresswoman Barbara A. Mikulski is facing Republican Ross Z. Pierpont and Independent Lawrence K. Freeman. The Baltimore Democrat is seeking a fifth term.

Maryland voters also will be asked to approve or reject a constitutional amendment that would bar from elective office anyone who at the time of his election is not a registered voter. Approval would close a loophole in state law under which former state Sen. Tommie Broadwater, who is on probation after his prison term for food stamp fraud, could run for his old seat as an independent.

Voters in Montgomery, Howard and Anne Arundel counties will also decide whether their county councils should be elected by district rather than at-large.

In Prince George's County, voters will have a chance to lift the absolute $143.9 million property tax limitation adopted in 1978. If approved, the charter amendment would freeze the tax rate at three cents below its current rate. Incumbent circuit court judges Arthur M. Monty Ahalt Jr. and G.R. Hovey Johnson are facing a challenge in Prince George's from county prosecutor Arthur A. Marshall Jr.

School board members in Howard, Montgomery and Prince George's counties will also be elected.