Barack Obama's surrogates are already setting the stage. The Democrats are now assured of a disastrous situation should Hillary Clinton manage to come back and win the nomination. Threats are now being made to make this year's Democratic Convention even worse that the 1968 Democratic Convention that was roiled with violence and controversy:

Allies of Barack Obama have warned of chaos if unelected "super-delegates" overturn the will of grassroots Democrats when the party chooses its presidential candidate at its national convention in August.

The Illinois senator is leading in the primaries battle for elected delegates but the contest could yet be tipped in Hillary Clinton's favour by nearly 800 party officials - known as super-delegates - who comprise a fifth of the overall 4,049 delegates voting at the convention.

Jim Doyle, the governor of Wisconsin, which holds its state primary tomorrow, said the party would tear itself apart if Mr Obama won the most elected delegates but lost the nomination. "It would be a disaster for the Democratic party to thwart what has happened in the caucuses and primaries," he told Fox News yesterday.

Concern is growing that the party could face a bitter and divisive convention if both candidates stay in the race. Douglas Wilder, the former governor of Virginia and now mayor of Richmond, raised the spectre of the acrimonious 1968 party convention in Chicago, which was marred by clashes between protesters and police as anti-war -Democrats feuded with party moderates.

"There will be chaos at the convention," Mr Wilder predicted, if super-delegates handed the nomination to Mrs Clinton. "If you think '68 was bad - look at 2008 and it will be worse." (Click "Read More" Below)

Mr Obama has a lead of at least 150 elected delegates over Mrs Clinton but the gap narrows to about 50 when super-delegate pledges are included. Mrs Clinton has so far won the declared support of about 230 super-delegates, while about 140 have endorsed Mr Obama.

The New York senator was expected to dominate among the super-delegates - who include Congress members, governors and mayors - because of her connections within the party hierarchy. But some super-delegates have raised the possibility of switching to Mr Obama if he wins a clear victory among elected delegates.

Mrs Clinton's backers said super-delegates were a legitimate part of the nomination process and warned the Obama campaign not to interfere with their role.

Some Obama allies have argued that super-delegates who have not yet made an endorsement should vote in line with their local primary or caucus results. The Clinton campaign insists that super-delegates should make independent judgments.

"Super-delegates are supposed to vote their conscience," said Howard Wolfson, communications director for the Clinton campaign, yesterday. "Our super-delegates are staying with us. We're not worried about that. Neither candidate will get to the [2,025 votes] needed to secure the nomination without the support of super-delegates."