Results show 48 percent of respondents favored Obama, D-Ill., the presumptive Democratic presidential candidate, while his likely Republican challenger garnered 38 percent, the Minnesota Public Radio and University of Minnesota Humphrey Institute poll released Thursday indicated.

However, pollsters said McCain-R-Ariz., could win the contested state if he taps Minnesota Gov. Tim Pawlenty as his running mate.

"This is not a poll saying Obama has a lock on Minnesota," said Larry Jacobs of the Humphrey Institute "So this race is very much up in the air and up for play."

Pawlenty is reported to be on McCain's short list of vice presidential choices.

"Our analysis suggests that the McCain ticket jumps by 13 points by adding Governor Pawlenty to the ticket," Jacobs said. "That is quite an impact."

The telephone survey interviewed 763 likely voters last week and early this week and has a margin of error of 3.6 percentage points.

The Republican National Convention will be Sept.1-4 in St. Paul, Minn.