Democratic Party leaders are concerned that the protracted battle for the nomination between Barack Obama and Hillary Clinton could damage the chances of either of them winning the presidential election in November.
As three more states voted yesterday, party officials were confronting for the first time the likelihood that by the time the last primary ballots are cast, the two candidates will have hammered one another to a standstill. That raises the highly unpalatable prospect that Democrats will have to wait until their convention in late August to identify the nominee. Worse, the final say may be left to a few hundred "super delegates" – senior party officials and Democrats elected to Congress or state governorships.
Rarely have conditions been so favourable for a Democrat to win the White House as in 2008. The economy is sputtering, and the Iraq war is only slightly less unpopular than the Republican incumbent who started it. But there are fears that this advantage could be eroded if the party cannot unite behind its candidate by early summer.
The spectre of an intense but inconclusive battle has loomed larger in the wake of last week's "Super Tuesday" clash, which was by any reckoning a photo finish. Mr Obama won more states; Mrs Clinton won the biggest states. By yesterday, Associated Press estimated he had won more delegates than she did on Tuesday – precisely two more.
On the Republican side, the primaries have fulfilled their function of throwing up one unstoppable candidate reasonably quickly. Although the Baptist preacher Mike Huckabee won the Kansas caucus yesterday, and vowed to fight on, there is no doubt that the nomination will go to Senator John McCain. Some Democrats fear that while their party remains divided, Mr McCain can use the time to solidify his support.
In the short term, the Democratic pendulum may swing Mr Obama's way. He is expected to win in Louisiana, a state with a large black population, where voters began trickling into polling stations before dawn yesterday. He campaigned here in New Orleans on Thursday, while Mrs Clinton skipped the state. Mr Obama was also considered to have the edge in Nebraska and in Washington state.
Although the two candidates were closer in Maine, which holds Democratic caucuses today, Mr Obama is favourite to gain the majority of delegates in the "Potomac primary" on Tuesday, when Washington DC, Virginia and Maryland go to the polls. Thus, while Mr Obama is about 70 delegates behind Mrs Clinton so far, he could well be ahead by the end of this week. He has also had extraordinary success in raising funds, an advantage that was amplified by Mrs Clinton's disclosure last week that she and her husband Bill had been forced to dip into their own fortune to lend $5m to her campaign.
Even Mr Obama knows, however, that delivering a knockout punch to his rival has now become difficult. Mrs Clinton is expected to draw level again in contests further down the line, such as Texas next month. Indeed, an internal campaign memo inadvertently attached to a press release last week showed Mr Obama's own aides are predicting that come the last of the state-by-state primaries on 5 June, he might be ahead of Mrs Clinton in delegates, but only by a hair.
This is the nightmare scenario now confronting the party. There will be options for resolving such a draw, but all are about as unappealing as the other, starting with offloading the final decision on to the 796 "super delegates". These are mostly elected members of Congress, governors and assorted party grandees. For them to choose between the two would look like a mockery of the democratic process.
"To the public that looks like a throwback to the old, corrupt system of smoke-filled rooms," noted Larry Sabato, a political scientist at the University of Virginia.
A less objectionable solution would be a truce between the two runners and the formation of a two-for-one "dream ticket". It's an idea Democrat voters mention often. Howard Dean, the chairman of the party, said last week that some kind of armistice would have to be negotiated if they are still tied in the spring.
But an even trickier problem is looming. Michigan and Florida leaned to Mrs Clinton in their primaries, but neither will be allowed to send delegates to the convention because they broke party rules by voting early. Mrs Clinton wants them seated, because they could break the draw. Mr Obama does not. It may take a court case to resolve this.
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