His perceived ability to defeat US President George Bush was the main reason behind Senator John Kerry's sweeping victories in this week's major primaries, Khaled Dawoud reports from Washington The "comeback candidate" is living up to his self-chosen nickname. By winning primary elections and caucuses in five out of seven states contested on Tuesday, Massachusetts Senator John Kerry consolidated his position as the Democratic front-runner in the race for the party's nomination to compete against US President George Bush this November. Last month, opinion polls showed Kerry lagging behind former Vermont Governor Howard Dean. But the Vietnam veteran and US senator of 19 years prevailed in the Iowa caucus and New Hampshire primaries last month, and, on Tuesday, Kerry won easily in Missouri, New Mexico, Delaware, Arizona and North Dakota. However, Kerry's main contenders insisted they would continue fighting for the party's nomination. After claiming victory in South Carolina, North Carolina Senator John Edwards stated he was still confident he could win the nomination "and beat George Bush". The first-term senator spoke of spreading a "message of hope", and highlighted his humble working-class background. Edwards also contrasted his southern origins to that of New England liberals such as Kerry and Dean. In Oklahoma, former General Wesley Clark narrowly beat Edwards and Kerry to capture his home state. Until recently, Clark was considered to be a major contender to Bush, because of his military background. The former front-runner Dean failed to even make a strong showing in any of the seven states. Although Dean expressed optimism about his chances in selected upcoming primaries, most political analysts tend to agree that Dean's chances are now slim, with the Democratic race practically confined to Kerry, Edwards and Clark. Tuesday's results also forced Senator Joseph Lieberman out of the race, after he placed a distant second behind Kerry in his home state of Delaware. Lieberman was criticised by most Democrats as being too conservative, after aligning himself with the Bush administration's "war on terror". Democratic voters cast their ballot in primaries and caucuses to elect delegates who will represent the different candidates in the party's national convention due to be held in Boston, Massachusetts on 26 July. A candidate needs to win 2160 delegates to win the party's nomination. At stake on Tuesday's elections were 269 pledged delegates -- 74 in Missouri, 55 in Arizona, 45 in South Carolina, 40 in Oklahoma, 26 in New Mexico, 15 in Delaware and 14 in North Dakota. After now having won seven states in total, Kerry has over 150 delegates, followed by Dean with 75, trailed by Edwards, Clark, House of Representatives member Dennis Kucinich and African- American civil rights activist Reverend Al Sharpton. The race turns next to Michigan and Washington on Saturday, with a combined 204 delegates. Nine more primaries or caucuses follow before a major showdown on 2 March, when populous California, Georgia, New York and Ohio join six other states at the ballot box. The remaining primaries take place between 9 March and 8 June, but a presumed nominee will likely be in place before then. In nearly every region of the nation, Democrats who cast votes this primary season said they had but one overriding priority -- to defeat President Bush in November. "Ability to beat Bush" was also the main reason cited in exit polls by Democrats who voted for Kerry. Democratic candidates, except for Lieberman, built their campaign around attacking the major policies of President Bush. Although Iraq still topped the agenda of "irresponsible and wrong" decisions taken by President Bush, the Democratic candidates have apparently recognised that voters in national elections would likely give priority to domestic issues such as education, health care and unemployment. Recent opinion polls indicate at least 55-60 per cent of Americans support Bush's decision to invade Iraq. While the failure to find alleged weapons of mass destruction in Iraq was embarrassing for the Bush administration, analysts believe that this will not be the major election issue in the upcoming presidential race. The results achieved by Kerry on Tuesday also confirmed his image as a national candidate who scored well among all categories of the American society. Kelly scored well among whites, blacks, elder citizens, younger citizens, war veterans, the less-educated and voters who called themselves moderate or conservative, according to exit polls, though Edwards split the African-American vote with Kerry. While acknowledging the victories of Edwards and Clark in South Carolina and Oklahoma, Kerry said that unlike other candidates, he was not "cherry picking" states where he could achieve victory. He said he was the only candidate to run serious campaigns in all seven states contested on Tuesday, proving he was "a national candidate". Looking beyond Tuesday, Kerry planned visits in Washington state and Michigan, where polls show him leading Saturday's caucuses. Edwards will skip ahead to Virginia and Tennessee, which have contests on 10 February. Both campaigns plan to air ads in the two southern states. In the run-up to Tuesday's election, the candidates stuck closely to their messages: Kerry railed against special interests; Edwards emphasised his small-town upbringing; Clark flashed his military medals; Lieberman offered a centrist alternative; and Dean cast himself as a Washington outsider. But their messages were not all positive. Edwards and Dean criticised Kerry's ties to lobbyists, ignoring their own connections to special interests, while Clark accused Kerry of flip-flopping on affirmative action. Kerry fought back by questioning Edwards' electability and credentials, saying this is not the time for "on-the-job training". Democratic leaders moved up several contests this primary season, hoping to unite the party behind a candidate early to challenge Bush, who has already raised over $140 million for his re-election bid. In polls held shortly after Tuesday's results, Kerry appeared to lead Bush by six percentage points if elections were held now. But White House officials said this was a normal result after the public was heavily exposed to Democratic campaigns where Bush was sharply criticised. They also used the same reason to justify Bush's drop to 49 per cent in overall popularity ratings; the first time he has fallen below the 50 per cent threshold since the 11 September 2001 attacks. Republican campaign officials said Bush will soon start a television advertising campaign to refute the charges made by his Democratic contenders.