The thrust of a comment by political consultant Robert J. Keefe about AFL-CIO President Lane Kirkland was reversed in an article Saturday. What Keefe said of Kirkland and the AFL-CIO presidential endorsement was, "He wants it to be clean and neat, so it embarrasses non-endorsed candidates as little as possible."

The AFL-CIO Executive Council probably will decide Tuesday to move up the date of the labor federation's controversial presidential endorsement from December, according to labor officials.

Former vice president Walter F. Mondale is favored to win the endorsement, engaging for the first time the AFL-CIO's political machinery behind one candidate long before the party choses a nominee. Advancing the date would give a timely boost to Mondale's faltering status as the Democratic front-runner.

Leaders of several major unions, pushing hard for such a move, will have little apparent opposition when the council's meeting opens in Boston on Monday. AFL-CIO President Lane Kirkland reportedly telephoned the 33 members and found all but a handful disposed to moving up the date.

However, summer gains made by Sen. John Glenn (D-Ohio), with his growing image as a voter favorite, have prompted some labor leaders to warn that the federation may be saddling up a losing horse if they rush to endorse Mondale. Glenn, once relatively aloof, recently has paid court to labor leaders and union groups.

And Sen. Alan Cranston (D-Calif.), the candidate to whom the labor endorsement is most critical, pulled out all the stops this week in his hardball challenge to the council to hew to the December date on grounds that they owe it to him.

Citing his record as a friend of labor, Cranston put it bluntly to a gathering of the United Food and Commercial Workers in Montreal: "Is it fair to change the rules in the middle of the game, for the benefit of one player, Mondale?"

Mondale supporters are pushing for the speed-up, he said, because they "feel time is running out on them." He noted that "every Democratic front-runner since 1956 has fallen by the wayside."

Cranston has barraged labor leaders with letters and telephone calls bearing the same appeal. He has also enlisted the backing of large home-state labor blocks in California, aides said.

Still, most AFL-CIO sentiment seems to be running in favor of a bold gamble. The oft-heard theme is that, given their disillusionment with their traditionally cautious and scattershot approach to presidential races, and the declines they have suffered under President Reagan, labor partisans have little to lose taking a high roll.

Said one member of the Executive Council who did not want to be identified, "I'm not sure this is the right thing to do. But at this point, if we're going to beat Ronald Reagan, the labor movement has to be mobilized and solid behind a candidate. We need a free hand and as much time as possible. Almost everyone believes we can get that kind of support behind Fritz Mondale the easiest . . . . "

"Sure it's going to be tough to cut Alan off," he added. "And sure, there's some feeling that Glenn might be the stronger candidate. But the question is, how are we going to be the most effective?"

"There's a good likelihood they'll advance the decision to the convention," said Communications Workers of America President Glenn Watts, a Mondale supporter. "It's logical."

Regarding the risk of rushing to the wrong candidate, he added, "I keep hearing that Democrats really think Mondale is the better man, but they're afraid John Glenn is more electible. Well, aren't we supposed to provide some leadership here?"

"I think they'll probably vote to move it up, even though I think the smart thing would be to hang loose until December," said Marty Hughes, an Ohio-based CWA official regarded as Glenn's point man in organized labor.

William Winpisinger, president of the Machinists Union, is partial to Cranston, but indicated this week that he will not resist the accelerated endorsement schedule.

Still, there was some hedging.

"It's not in the bank yet," said Mondale aide Paul Jensen. "It's hard to count votes on this one, because a different dynamic builds in the council meeting. Lane is much more consensus-oriented than Meany was," referring to his predecessor, the late George Meany.

The labor chiefs may vote to move the decision to a specific time, such as the first week in October, when the federation's convention is scheduled. Or they could leave the date to Kirkland's discretion, officials said.

In the view of Glenn aide Robert Keefe, Kirkland "wants it to be clean and neat, so it embarrasses non-endorsed candidates as much as possible. And wants to keep it neat and clean on the inside, too. So he wants to keep it away from the convention."

Mondale supporters, however, favor doing it in time to use the convention for a splashy Mondale kick-off.

Through the summer dog days, Kirkland has managed to hold his generals to their pledge of official silence regarding their unions' candidate preferences, even as the results of various regional conferences, newsletter straw polls and other rank-and-file pulse-taking are tallied.

This self-discipline was in part a bow to Cranston. With the American Federation of State, County and Municipal Employes and other big unions poised to endorse Mondale last spring and give the early appearance of a bandwagon, Cranston last winter made his first dramatic and successful appeal to labor leaders to give him a chance.

But they are growing restive, and expect the lid to be off after this week's council meeting.

Meanwhile, the labor federation's political operatives have spent the summer educating their field commanders across the country in the complexities of the Democrats' delegate-selection processes state by state and otherwise honing their grass-roots forces for the uncommon effort they believe it will take to beat Reagan.