In a move that will spark speculation about Mitt Romney mounting a late challenge in states that had appeared out of reach, President Obama's campaign has purchased television advertisements in Minnesota, according to an Obama source.
The source described the ad buy in the Minneapolis market as "very small" and added that it is targeted primarily at voters in the neighboring swing state of Wisconsin. Minneapolis television reaches Wisconsinites who live in the northwestern part of the state, according to the source.
But the decision to invest in Minnesota will stir talk that the president is now playing defense in a place that had long been considered a lock for him.
The Associated Press reported earlier on Friday that the Romney camp was placing its own TV ads in Minnesota -- a move that also may be directed at Wisconsin voters but nonetheless suggests unexpected strength for the Republican.
Romney's campaign announced Thursday that it and its affiliated committees had approximately $169 million on hand to spend over the last 10 days of the race.
The Obama campaign has previously aired advertisements on cable TV in Minneapolis and on the radio in Duluth, also in order to reach the Wisconsin electorate.
Romney has not led in a single Minnesota poll all year and trails Obama by 7.3 percentage points in the latest RealClearPolitics Average of Minnesota polls.
Neither Obama nor Romney has visited the state recently, but Vice President Biden's wife, Jill Biden, campaigned in Minneapolis and Duluth earlier this month.
In Wisconsin, Obama leads Romney in the RCP Average by 2.3 points.