The latest poll is really two polls in one. The first of about 350 likely voters was taken between last Monday and last Wednesday -- before Thursday's vice presidential debate between Democrat Joe Biden and Republican Sarah Palin.
But the numbers changed among more than 400 likely voters who were interviewed after the debate through the weekend.
"After the congressional enactment of the financial rescue plan and vice-presidential debate, Barack Obama shot out to a 14-point lead," said Larry Jacobs, from the University of Minnesota's Humphrey Institute.
Jacobs said the main reason for the dramatic shift in the race last week is the economy. Voter confidence in how Obama would handle the financial crisis went from a three-point margin over McCain to a 14-point margin.
And, while a bulk of the attention was on Alaska Governor Sarah Palin's performance in the vice-presidential debate, Jacobs said the poll found that more people were impressed with Delaware Senator Joe Biden's performance.
"We see that Biden boosted the Obama ticket by about 18 points," Jacobs said. "He also improved his image and evaluation among voters for caring, for having centrist political attitudes, for honesty and for experience. All of those factors seemed to play into the fact that Biden was seen as more appropriate for president and helped his ticket more than Palin did for the McCain ticket."
The Obama campaign's Minnesota director, Jeff Blodgett, said the campaign isn't putting much stock in any one poll. But, he said the findings aren't a big surprise since the economy has been on the top of voter's minds throughout the year.
"As they tune in and as they are concerned about the economy, they're asking the question 'Which candidate is better able to handle the economy going forward and to get us out of this economic mess?'" Blodgett said. "And overwhelmingly, we are finding that voters are coming toward Barack Obama."
McCain's Regional Campaign manager Ben Golnik questioned the poll's findings, suggesting that too many Democrats were interviewed after the debate. But, he agreed with the findings that one in five voters could change their mind before election day. He said McCain will make his case directly to those voters when he visits Lakeville later this week.
"I think the race is extremely fluid at this point We feel good about where we are," Golnik said. "We have John McCain coming into town this Friday and that's going to be to target those undecided voters, those voters who have not made up their minds yet."
Golnik also argued that it's clear that the race is competitive since some polls show the race as a dead heat in Minnesota.
Mark Blumenthal, editor and pollster at Pollster.com, said those confused by the varying poll results shouldn't focus on just one poll but on what a variety of polls show.
"It you step back and kind of squint at the data, you're in a better position to try to ignore the noise and variation and focus on the underlying consistency in the polls to the extent that it exists," Blumenthal said.
It's clear that both campaigns consider Minnesota vital to winning the White House. The McCain campaign recently opened six more offices and will add up to ten staff members to help turnout the vote. The efforts come after McCain's campaign announced that they will pull money and manpower out of Michigan and will reportedly direct those resources toward Minnesota and other battleground states.
Another signal that the race is competitive is television ad spending. McCain and the Republican National Committee have spent at least $2 million in television advertising in the Twin Cities since June.
Obama also started running ads in the Twin Cities last week, the first time since he won February's precinct caucuses. He also told reporters last Wednesday that he intends to make a campaign stop in Minnesota between now and election day.
Editor's note: Information about how the joint Minnesota Public Radio/University of Minnesota Hubert H. Humphrey Institute poll was conducted is available here.