Rep. Gladys Spellman remained in critical but stable condition at Greater Laurel-Beltsville Hospital yesterday, semiconscious and apparently aware of her surroundings.

Hospital authorities monitoring the representative's medical progress continued to say that Spellman, 62, had shown gradual improvement since Friday evening when she was struck down by heart arrest during a campaign appearance at a children's Halloween costume judging at a Laurel mall.

Buoyed by word of her improved prognosis, Spellman's political associates and supporters, including Lt. Gov. Sam Bogley, former state Senate President Steny Hoyer and former County Executive Winfield Kelly Jr., used the occasion of a county Democratic pep rally Saturday night to offer prayers for her recovery and deliver an emotional demonstration of support.

Yesterday Spellman, who is expected to be easily reelected Tuesday in the state's Fifth Congressional District, remained in what her doctors have characterized as a "sleep-like state," unable to talk but seemingly aware of her surroundings.

During the gathering of some 200 Democratic activists at Prince George's County Community College, Edna McClellan, an aide who is one of the congresswoman's closest friends, reassured party loyalist that Spellman "is winning the most important battle [for her life]. She needs and we ask for your prayers and your support."

McClellan said later that Spellman seemed to recognize her when she sat next to her hospital bed in Laurel's coronary care unit. The cardiologist's statements Saturday, the first optimistic note concerning Spellman's condition, convinced the family and friends who have maintained a constant vigil outside her room that Spellman will pull through, according to McClellan.

At the rally county politicians said they felt certain that Spellman would survive her illness, "get a tribute from the voters" on Election Day and defeat her little know Republican opponent Kevin Igoe by a landslide. Igoe, who was not expected to do much better than other challengers Spellman has trounced in the past, announced this weekend that he has ceased all campaign activity as a result of Spellman's illness.

According to her cardiologist Michael Schwartz, the hospital initially thought Spellman had suffered a massive heart attack but by Saturday had determined that she had been struck down by heart arrest, a stoppage of the heart that deprives the brain and other vital body organs of the blood and oxygen they need to operate.

Schwartz said that his tests have determined that Spellman's heart was not injured during the incident but there is no way of knowing yet whether Spellman's brain and other organs were affected by a lack of blood and oxygen. s

Her illness stunned the Prince George's political establishment because of Spellman's status as the county's most durable and popular Democratic politician. Her removal from the scene for whatever reason would force a special election to be held to find a successor, an event that would throw the county into political turmoil.