President Carter helicoptered to a dairy farm outside Columbia last night for a 10-minute appearance, and Maryland's Democratic leadership from all over the state seized on the event to kick off the state campaign.

Carter hardly had time to shake the hands of the 30 elected officials who came to see him before departing for a nearby Willie Nelson concert and Democratic National Committee fundraiser where he was ushered on stage to the strains of "Amazing Grace," a Southern hymn.

The earlier brief encounter at the home of State Senate President James Clark, party leaders said, is likely to be all the campaigning the president does this fall in Maryland, a state with 10 electoral votes and a long Democratic tradition. "The national strategists have us down as a strong and relatively safe state," one state coordinator shrugged.

But even before the president's helicopter appeared, many of the assembled Democrats had made clear they did not share the confidence that the president's schedule implies. Maryland may be counted as one of the eastern industrial states that Carter must assume he will win, but the campaign of independent John Anderson and Republican Ronald Reagan's appeal to the state's blue-collar voters have cause the local Carter supporters to believe the Maryland race is even -- at best -- as their campaign begins.

There is little reason to believe the Maryland race will not stay close, leaders of both presidential campaigns say. Reagan also plans only one short stop in the state -- for the presidential debate next week -- while Anderson's forces are planning a relatively strong effort that they believe will prevent his substantial support in mid-summer polls from eroding.

In fact, coordinators of all three campaigns say that while voters are left to watch the candidates on network television, the real competition in Maryland is likely to come down to targeted, get-out-the-vote drives on election day.

"We could knock on every door between now and November and not change a single vote," said state Del. Charles Ryan (D-Bowie), who will help coordinate the Carter campaign in Prince George's County. "The key for us is to find who our voters are and then make sure they go to the polls."

Both the Reagan and Carter campaigns are already focusing on the vote-targeting effort. In Montgomery County, for example, Democrats are conducting a registration drive at apartment buildings in the eastern end of the county -- where the heaviest concentration of likely Carter voters is believed to be -- while in Prince George's, Republican Executive Lawrence Hogan has sent out 400 letters to his regular contributors in an effort to raise $16,000 for a Reagan phone bank.

Statewide, the Carter campaign is compiling lists of precincts that have voted heavily Democratic in past presidential elections. Those areas will get the first phone banks and registration booths. "It's only logical in a campaign like this to look at how people have traditionally voted, and direct your effort on that basis," said David Doak, who is Carter's new campaign manager in the state.

For Carter, those areas begin in Baltimore City -- which voted for Carter two to one over Gerald Ford in 1976 -- and end with Montgomery and Prince George's, which gave Carter the rest of his 6 percent winning margin in the state.

Meanwhile, Don Devine, Reagan's campaign manager, expects to concentrate on the Eastern Shore, rural areas and Baltimore County -- which Ford won in 1976 -- along with eastern Baltimore City, where Devine believes Carter may be most vulnerable among blue-collar steel and port workers.

As in many states, however, Maryland's historic voting patterns may be skewed by Anderson, who received 10 percent of the vote in last May's Republican presidential primary and was running first in Montgomery County -- with Carter third -- in a poll done by Democratic Rep. Michael D. Barnes in July.

"Maryland is a priority state for us," said Mary Saner, Anderson's coordinator in Montgomery. "We're going to be directing a lot of effort here because it's one of the states we think we can win."

Unlike the Reagan and Carter campaigns, Anderson's state managers are depending heavily on the prospect of local media coverage. "Local media spots that make us look serious are going to make or break our campaign," said campaign manager Jim Kennedy. Anderson will make several trips into the state in the hopes of prompting television exposure his campaign could not otherwise afford to buy, Kennedy said.

The Anderson campaign must also worry about raising money, and has been preoccupied with art shows and small events -- like a showing of the Reagan-starring movie "Bedtime for Bonzo" in Columbia Friday night -- that have raised about $7,000 so far.

Both the Reagan and Carter campaigns are also planning media-directed campaign days for state elected officials and surrogates like Vice-President Walter Mondale and Nancy Reagan, but with the candidates themselves absent, such events are likely to be of secondary importance.

There will be no-shows on both sides, too. Republican U.S. Sen. Charles McC. Mathias has declined to join the state Reagan steering committee or appear at Reagan events so far, while Montgomery's Rep. Barnes, a leader of last summer's "open convention" movement in New York, has said he will support Carter but is unlikely to actively campaign for him.

The uranium, packed in special protective cylinders on a flat bed, was found Wednesday night still on the truck, which had been abandoned alongside the U.S. 460 Bypass in Blacksburg. The driver was gone, and two tires were missing.

U.S. Department of Energy officials said the low-level radioactivity of the fuel posed no health or safety hazard, but they say they are concerned about "sloppy handling" of radioactive material by the trucking company.