The US Vice-President, Mr Al Gore, and Mr George Bush, the Governor of Texas, wasted little time in criticising each other's policies on the morning after their big wins in the Democratic and Republican primary elections.
Both are now certain to be the candidates of their parties in the presidential election on November 7th after repulsing challenges on "Super Tuesday" from former Senator Bill Bradley and Senator John McCain respectively.
Mr Bradley, who lost the Democratic contests in all 15 states on Tuesday, is expected to announce his withdrawal from the campaign today and to endorse Mr Gore. But he has ruled out being Mr Gore's running mate if asked.
Mr McCain, who lost to Mr Bush in California, New York and Ohio and six smaller states, spent yesterday consulting advisers on whether to continue his campaign. His only successes came in four New England states, Massachussets, Connecticut, Rhode Island and Vermont where independents were allowed to vote with Republicans.
He is facing further defeats in Texas, Florida and other southern states next week and is likely to withdraw from what has been a roller-coaster contest since the New Hampshire primary five weeks ago. The third Republican candidate, Mr Alan Keyes, may continue but without affecting the outcome.
Mr Bush replied scathingly to Mr Gore's proposal yesterday to end the raising of so-called "soft money" and to replace TV ads with weekly debates. On ABC's Good Morning America, Mr Bush said that the Vice-President was "trying to make America forget what went on in Washington D.C. for the past eight years. Americans aren't going to forget". Mr Bush said that he felt "battle-tested" and that "People saw I could get whipped and bounce back."
Following the Tuesday primaries, Mr Bush won at least 447 delegates bringing his total so far to 617 of the 1,034 needed to win the Republican nomination at the convention next August.
Mr Gore gained at least 936 delegates on Tuesday bringing his overall total to 1,418. He needs 2,170 to win the nomination.
Mr Gore said yesterday in interviews that Mr Bush was out of touch with the electorate in his support for the National Rifle Association, on social security reform and refusal to ban "soft money" contributions.
Referring to the economic situation when Mr Bush's father was president, Mr Gore said: "We need to build on our record of prosperity. We don't need to go back to where we were eight years ago. They tried their approach before; it produced a triple-dip recession and quadrupled the national debt."