"REMEMBER WHERE you heard it first," the old journalistic vanity goes -- meaning: I thought of it, or I found it out, or I put it all together in the first place. Sen. Edward Kenedy is suddenly plying the same line. This began in his recent Georgetown University speech when he appropriated as his own proposal one that had been under negotiation among the parties to the Iranian conflict since shortly after the hostages were seized last November.

But from the Georgetown speech's tentative expropriation of the proposal -- without due political compensation to those who thought it up or were then bargaining it out -- he has moved on to make what, in another context, would be known as a preemptive strike: if it's likely to work, if it looks as though it may result in the freeing of the American hostages -- well, bless my stars, if Sen. Kennedy didn't (according to the senator) either think it up or push the president to take it up. Mr. Kennedy even suggests that had Jimmy Carter not taken so long to see the virtue of the "Kennedy" proposal, the crisis would surely not have dragged on so long.

It is a little bit weird. Half the time the senator is lamenting the horrible failings and inadequacies beyond description of the Carter administration in its international dealings. The other half he is taking credit for its successes. He deplores its sluggishness and lack of ingenuity in dealing with the world, while simultaneously positioning himself to take bows for whatever future achievements its mollusk-like diplomacy may produce. Needless to say, the closer the administration appears to get to the release of the hostages, the more strident and patronizing the senator's remonstrances become.

Meanwhile, back at the White House -- the one that is being fought over but which, to the best of our knowledge and belief, still houses Mr. Carter -- it is being said that the senator is doing the nation a grave disservice and so forth by this pretense of being the savior of our policy. Even while criticizing the senator for his spoiling tactics, however, the administration is arguing defiantly that its policy had not been spoiled. On the contrary, the president wants all of us to understand that, notwithstanding the rude jostling he has received from his challenger, he is proceeding with apolitical dexterity, wisdom, vision, patience, firmness, fortitude and restraint toward what he (and we and Sen. Kennedy and everybody else no doubt) hopes will be the prompt release of the hostages.

Yes: we know there are some grim, dead serious issues involved. Mr. Kennedy does, as the president points out, imply recklessly and falsely that the Soviets and the Iranians who caused the trouble in Southwest Asia are less at fault for what has happened than is the president. And Mr. Carter's identification of attacks on him with attacks on the "national interest" is not exactly a disinterested or particularly compelling response. But dead serious or farcical, the question is the same and it remains: Can a democracy as unruly as our own conduct a presidential campaign and a delicate diplomatic negotiation at the same time? Stay tuned.