Another poll points out marginal difference between Democrat and Republican candidates for elections to be held, in November, in the swing states.

The "Big Ten" poll, conducted by the University of Wisconsin political science department, covered the eight states of the Big Ten conference and revealed that Barack Obama and John McCain are statistically tied in seven of the eight Midwestern states.

Obama seemed to have slight advantage over McCain in Wisconsin, Michigan, Ohio and Minnesota. But they were tied in Pennsylvania and Iowa, while McCain held the lead in Indiana. In Obama's home state of Illinois, the Democrat led 53 percent to 37 percent.

“The close margins in the vast majority of states show that whatever the effects were immediately after the national party conventions, these states have moved back to a highly competitive status, with neither candidate having a clear lead, except in Illinois,” said Charles Franklin of the University of Wisconsin and poll director.

The poll, which had a margin of error of 3 percentage points, shows Obama with a 1-percentage-point margin over McCain.