When a group of Maryland Republican leaders arrived in Rockville yesterday to boost the party ticket, they found themselves on the county courthouse steps addressing two reporters and one bedraggled, somewhat incoherent street person who happened to wander by.

The reception by the lawyers and courthouse employes inside was only slightly better. Most people smiled politely, some agreed with the group's sentiment and a few others were having none of it.

"ReaGUN, ReaGUN, ReaGUN," said one sheriff's department employe jokingly as one of the group tried to hand him some campaign literature. "I don't even want to talk to you. Get them out of here. Bedtime for Bonzo, right?"

The state Republican party executive director, Tom Buckmaster, just sighed as he watched and then began corralling the group onto its next event. "Well, they can't all be friendly, right?" he said.

The group, which called itself the Republican "truth squad," was in Rockville as part of a two-day, seven-county tour of Maryland to bolster the Republican ticket and counter a similar trip through Maryland last week by the state's top elected Democrats.

But while the Democratic show featured the governor, attorney general, secretary of state, comptroller, U.S. senator and one of its members of Congress, the Republicans, heavily outnumbered on Maryland's voter rolls, had to reach further down the political hierarchy. They could only draw on two county executives, including Prince George's Lawrence Hogan, former senator J. Glenn Beall and a host of state delegates and senators.

Not even the top elected Republican in the state, U.S. Sen. Charles McC. Mathias, who is running for reelection, was there.

"Mathias is out hunting ducks where the ducks are, Baltimore City," said State Sen. Howard Denis (R-Mont. Co.). "That's why he's not here."

Those who did make the tour of western Maryland Thursday and Montgomery, Prince George's and Baltimore counties yesterday said they hope their effort will draw undecided voters and disgruntled Democrats into the Republican camp.

"We were getting polling information telling us that despite the 3-to-1 Democratic registration in the state Reagan could do very well," said Buckmaster. "The idea was to follow up on the debate in an effort to sway undecided voters. A Republican victory in Maryland is predicated on a strong showing in western Maryland and the suburbs and cutting our losses in Baltimore City [where the group did not go]."

In addition to spreading the Republican message, the tour also appeared to allow several members of the group, including Beall, Hogan and Anne Arundel County Executive Robert Pascal, to test voters across the state for a response to their own future candidacy for state office. Hogan, who is toying with running for governor or senate in 1982, brought several staff members with him to the various county appearances.