[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2008/images/09/11/art.cands.gi.jpg caption="New polls show a shift in one battleground race."](CNN) — Barack Obama appears to be holding on to a significant edge in Iowa in new poll numbers released this weekend, but his advantage over John McCain in Minnesota, which hosted the Republican convention earlier this month, seems to have evaporated.
Obama, who won the Iowa caucuses in January, has 52 percent of the vote in that state to McCain’s 40 percent among likely voters in a Des Moines Register poll conducted September 8-10. A CNN/Time/Opinion Research Corporation poll conducted August 31-September 2, during the GOP convention, showed a 15-point advantage for Obama, 55 to 40 percent over McCain.
But in Minnesota, where McCain accepted the GOP nomination this month, Obama’s 12-point edge in the last CNN/Time/ORC survey – also conducted during the Republican convention - has disappeared in a new Star Tribune survey: that poll finds both men tied at 45 percent each among likely voters, with 10 percent unsure.
During the convention, Minnesota Governor Tim Pawlenty said he thought his state "would be open to a candidate like Senator McCain" - but added that he believed "Democrats still have an advantage here."
Both surveys have a margin of error of plus or minus 4 percentage points.
Election Center: Check out CNN's electoral breakdown
CNN/Time/Opinion Research Corporation surveys earlier this month also suggested tight races in four other battleground states: New Hampshire, Michigan, Virginia, and Missouri.
Those polls showed slim advantages for Obama in New Hampshire and Michigan, while McCain was narrowly on top in Virginia and Missouri.