MIAMI -- Facing the possibility that his candidacy has but two weeks to live, Sen. Robert Dole's advisers are desperately trying to draw distinctions, based mainly on personality, with front-running Vice President George Bush.

It is a daunting task for the Senate minority leader. Short on money and organization, his high command is divided on strategy. In trying to break down Bush's southern ''fire wall,'' Dole propounds no great philosophical positions. He calls on the Republican faithful to abandon their heir apparent because ''the difference is leadership.'' More than disagreeing with Bush, Dole dislikes him at the level of contempt.

Bush's handlers laugh it off, reinserting their candidate in a vice presidential bubble. TV and radio spots respond to Dole's attacks while Bush sticks to generalities and avoids self-damaging remarks. It is an undemanding campaign, hardly preparing the vice president for opposing the Democrats. But that's not what's at stake in South Carolina March 5 and in the 20 Super Tuesday states three days later.

Of 840 delegates up for grabs in those 21 states, Dole will be happy to limit Bush to around 500 delegates. That is the price of Dole's fateful loss in New Hampshire, Pat Robertson's underachievement in the South and the virtual end of Rep. Jack Kemp's candidacy. Dole seeks an upset in Illinois a week later, to be followed by other midwestern wins, making it close enough for California to become the showdown primary June 7.

It is a very long shot, partly because there is no strategy consensus in Dole's campaign. He began the week in Atlanta addressing the Georgia legislature; traveled to Jackson, Miss., for a midday rally where the news media outnumbered supporters; and doubled back east for a sparsely attended rush hour rally in Fort Lauderdale, Fla.

In those states and everywhere else in the Super Tuesday South, Bush's leads are immense. His 2-to-1 Florida margin could sweep all 82 delegates. That leads to advice inside the Dole campaign to abandon Dixie forthwith and take a life-or-death stand in Illinois. But campaign manager William Brock operating from the plane, wants to nickel-and-dime Super Tuesday delegates in North Carolina, Missouri, Oklahoma and, maybe, Alabama.

No less difficult than deciding where Dole goes is determining what he says. In the South, he sounds more like a conservative. At that dreary Fort Lauderdale rally, he derided Bush's plea to ''give peace a chance'' by saying Gorbachev, Castro and Ortega only understand ''the point of a gun.''

But Bush, too, has turned right here, so Dole's distinctions mainly claim he is a self-made man, tougher and more effective. Commercials showing Bush as an ineffective waffler are appearing throughout the South. To portray the vice president as effete, one spot that started airing Thursday in South Carolina began, ''Here's another reason to vote for George Bush. He speaks French.'' He was then quoted as saying: ''C'est la vie'' when ''asked about his disagreement with South Carolinians on textiles.''

But again, Brock strategy is not set. Should scarce money be spent to cut losses in the South or hoarded for the midwestern showdown? Dole strategists hope these spots will prompt Bush campaign manager Lee Atwater to follow his instincts and open his war chest for counterattacks.

He has done just that. In South Carolina, Gov. Carroll Campbell complains in a radio spot that ex-U.S. trade representative Brock ''wouldn't get tough'' enforcing textile agreements. Another South Carolina spot claims Minority Leader Dole defected from President Reagan 30 percent last year. The same ''straddle'' spot that caused Dole to call Bush a liar over NBC in New Hampshire is repeated throughout the South.

It will take lots more than that to break Bush's campaign bank. The vice president himself is kept clear of nasty talk. In two days on the road beginning the week, he had scant contact with reporters.

In rally speeches, Bush does not have much to say about anything. He is back in his pre-Iowa bubble. A campaign with Air Force Two, long, black limousines, endless caravans, squadrons of motorcycle police and Secret Service platoons seems a different breed from Bob Dole's frantic, hastily arranged travels.

The vice president's men predict that the last intra-Republican debate has been held. That is in keeping with a campaign geared to prevention of some untoward event enabling Dole to recover from his New Hampshire fiasco. Whether it has the right stuff for the fall campaign could be quite another matter.