Now the uncertainties that would accompany an opposition victory have become a conspicuous element in the campaign itself.
Parliamentary results also indicated an opposition victory.
The military, with its history of sudden intervention, is said to be fretting about a possible opposition victory.
He pledges to provide stability, warning that an opposition victory would mean "chaos."
The prospects for a first-round opposition victory, however, are hardly promising.
In South Korea, military officers, worried about an opposition victory, talk about blocking this week's elections.
Milos Cervenic, 26, a metalworker, spoke hopefully of an opposition victory.
But they said the Government must recognize what monitors say was an opposition victory.
In 1999, in spite of dramatic opposition victories, 61 percent still consider elections to be fraudulent.
The breadth of the opposition victory appears to have stunned and divided the ruling coalition.