Among former Clinton supporters interviewed for the poll, 81 percent said they would vote for Obama -- a jump of 11 percent in a poll taken before the convention, USA Today reported Tuesday.

The convention succeeded in convincing more disaffected Clinton primary voters that Obama is a strong, decisive, honest and trustworthy leader, USA Today reported.

Twelve percent of Clinton primary voters questioned for the new poll said they planned to vote for John McCain, the presumptive Republican nominee -- a drop of 4 percentage points from the poll taken before the Democratic primary.

The poll was based on telephone interviews conducted Saturday and Sunday with 1,835 registered voters and has a 2-percentage-point margin of error.