Former president Gerald R. Ford propelled himself to the brink of active candidacy today, declaring that he would feel "an obligation" to enter the 1980 presidential campaign if those who have privately urged him to run will now do so publicly.

Meantime, in Washington, the formation of a Draft-Ford Committee was announced by former secretary of the Air Force Thomas C. Reed, who said the group hoped to demonstrate the "broad base of support" for a Ford candidacy.

Cranking the public media blades that he hopes will produce a presidential draft, Ford said he believes there is a "fair possibility" that he can win the Republican presidential nomination on the first convention ballot despite a decidedly late entry into the campaign.

The former president appeared tanned, fit and eager to run as he played the role of his own political pitchman at a news conference on the campus of Eckerd College, where he was spending the day lecturing to students. He also gave a speech to the general public tonight in the downtown Bayfront Auditorium, focusing on the problems of leadership in Congress.

"The most important point is that the polls reflect that I would be the most electable Republican candidate against the Democratic nominee," Ford said earlier today. It was a theme he repeated several times.

Ford said he will make his final decision on whether or not to run within the next two or three weeks." . . . The truth is that I would feel an obligation if there is a legitimate, broad-based, in-depth request from responsible people" to become a presidential candidate, he said. "I'm just old-fashioned enough, I guess to respond to that kind of request."

Throughout his news conference, Ford elaborated on this theme -- and each time he did so, he seemed to move himself closer to an active candidacy.

So the political future of the former president has come down to this: Ford will either declare himself an active candidate and fight an uphill battle for the nomination, or he will have to make an announcement that would be politically awkward for a former president, in which he would have to admit that he could not win sufficient backing from his friends and party stalwarts.

The political columnists Rowland Evans and Robert Novak reported today that Ford has decided to run, barring the unexpected, and that he will make his announcement on March 20. Here today, however, Ford said he thought the odds on his running were "50-50."

The key figures in the Draft-Ford Committee are Reed, a former Republican national committeeman from California, and John O. Marsh a former representative from Virginia who served as an assistant to Ford in the White House and now practices law in Washington.

Other members of the group include Sen. Harrison H. (Jack) Schmitt (R-N.M.), Rep. Bob Wilson (R-Calif.); business men Neil Bogart and Leonard Firestone, both of Los Angeles, Max Fisher of Detroit, Trammel Crow of Dallas, B. K. Johnson of San Antonio, Art Modell of Cleveland, banker Robert Price of New York; and Republican fund-raiser Lynn Meyerhoff of Maryland.

The group scheduled a news conference for Monday to announce its plans for encouraging Ford to enter the race.

While Reed and Marsh and several of the others on the draft-committee have played a significant role in national Republican politics, many of those who have been involved in past Ford campaigns have declined to endorse the draft effort.

It was learned today that House Minority Leader John J. Rhodes of Arizona had rejected an invitation to join the committee. Rhodes reportedly shares the viewpoint of former secretary of defense Melvin R. Laird, another longtime Ford supporter, that it is too late in the nominating process for Ford to gain a majority of the delegates and that his entry this month would produce a sharp intra-party split with supporters of Ronald Reagan.

Ford said that he talked to Senate Minority Leader Howard Baker (Tenn.) yesterday a telephone call that Baker initiated to explain why he was withdrawing from the presidential race.

But Ford said that he did not discuss with Baker whether the Senate minority leader would support a Ford candidacy.

Ford also said that it is "probable" that he will confer shortly with John Sears, who ran Ronald Reagan's 1976 campaign against Ford and who was recently fired as Reagan's 1980 campaign manager. Ford said he wanted to get Sear's views on the 1980 presidential campaign. "John is an old friend," Ford said. "We had some differences in 1976, but he's a professional in the political arena." Sears has been reliably reported to be in California waiting to meet with Ford.

In Washington, Charles Black, another ousted Reagan aide, denied a Washington Post report that he was ready to meet with Ford to discuss a possible campaign.

In making a late entry into the race, Ford would face formidable obstacles.

Filing deadlines have passed for 21 primaries in states which will be sending 908 of the 1,994 delegates to the Republican National Convention and the late-season state primaries of May and June proved in 1976 to be Reagan territory, as the California defeated Ford by 553 delegates to 446 in those states.