WASHINGTON -- Gov. Bill Clinton of Arkansas has seized an impressive but not necessarily irrevocable lead in a contest for the Democratic presidential nomination that may run through April into May or June.
Mr. Clinton's sweep of the southern primaries on Super Tuesday left his principal rival, former Massachusetts Sen. Paul E. Tsongas, in the dust. But continuing questions about Mr. Clinton's electability and the peculiarities of the Democratic nominating process made it unlikely there will be a quick knockout.
Meanwhile, President Bush continued his irrevocable march toward renomination for a second term, winning eight Republican primaries by huge pluralities that threatened to strip the last shred of political credibility from his conservative challenger, television commentator Patrick J. Buchanan.
As has been the case in virtually every Republican test this year, Mr. Bush suffered the embarrassment of defections far greater than had been expected from an incumbent president. But there were no figures to support Mr. Buchanan's insistence that his campaign is gaining steam, and the challenger was being faced with a put up or shut up situation in the Michigan primary next Tuesday.
Mr. Buchanan told supporters that the president has been "winning votes but we have been winning the hearts of the American people and we are going to continue to do so."
The most significant contests, however, were on the Democratic side, where Mr. Tsongas managed to salvage victories only in his home state of Massachusetts, neighboring Rhode Island and caucuses in Delaware. Thus, the pressure intensified on Mr. Tsongas to turn the campaign around in either Illinois or Michigan next week.
But Mr. Clinton remained far short of the 2,145 delegates needed to win the nomination. And it seemed unlikely he could reach that goal before running the course of the major state primaries ++ in New York and Pennsylvania in April, Ohio in May and perhaps even California and New Jersey on June 2, the final day of the primary season.
One key factor in the political arithmetic is a Democratic system that makes almost 18 percent of the delegates officially "unpledged" -- meaning that even those who declare a preference for a candidate are not legally bound to vote for him. That group includes all 400 members of the Democratic National Committee, 245 House Democrats yet to be chosen and other party leaders and officeholders.
The same freedom of action also is available to those elected as "uncommitted" and to those elected under the banner of the two candidates already driven to the sidelines, Sens. Bob Kerrey of Nebraska and Tom Harkin of Iowa.
Mr. Clinton's march also is being slowed, if only marginally at this point, by the candidacy of former Gov. Edmund G. "Jerry" Brown Jr. of California. Although Mr. Brown was skunked in the South, he showed in Massachusetts and Rhode Island that he is capable of getting the 15 percent of the vote that under Democratic rules entitles any candidate to a share of the delegates. And the states considered most receptive to Mr. Brown's unorthodox politics still lie ahead -- including Michigan, Wisconsin, New York, Oregon and California.
The role of the uncommitted may be enhanced by the fact that Mr. Clinton has not yet answered all the questions among Democratic professionals about whether he is carrying too much political baggage to be a viable opponent against Mr. Bush in November. Democratic leaders are licking their chops at the prospect of a vulnerable incumbent, but not yet persuaded that the Gennifer Flowers episode and Mr. Clinton's draft history may not be heavy weights to carry against a president who makes no bones about his willingness to do whatever it takes to win.
Mr. Clinton suggested in his victory statement that his Super Tuesday success had resolved the doubts about his electability. "The people of the South heard the worst about me, but they saw the best," he said. The private assessments of leading Democrats, including some supporting Mr. Clinton, made it clear, nonetheless, that more evidence is needed.
But if Mr. Clinton is not yet being universally embraced within the party, the same is clearly true of Mr. Tsongas, who still must persuade the political community that he can sell himself to constituencies of voters who don't know him as well as those in New Hampshire and Massachusetts. Mr. Tsongas did win the Maryland primary and caucuses and primaries in some small Far West states. But his credibility obviously depends on his ability to reach blue-collar Democrats in industrial states such as Illinois and Michigan.
Meanwhile, Mr. Bush was faced with the prospect of marching downhill to his renomination. Despite the president's big wins last night, his strategists were facing up to declining approval ratings by planning to cut back on his personal campaign schedule. It was a tacit admission that although there is nothing to fear directly from Mr. Buchanan, the conservative challenger has exposed a weakness that the White House must confront in the general election.