A study from the University of Wisconsin out today says that from Oct. 21-28, 63% of the Obama ads and 79% of the McCain ads were negative. In its previous report, about ads running from Sept. 28 to Oct. 4, the project said that 100% of the McCain campaign's ads and 34% of the Obama campaign's ads were negative.
The latest study doesn't fully capture some of the dramatic upturn in ad spending this week as the Republican National Committee increased its ad buys and the Obama campaign ran its half hour of network TV.
Still, it offers a snapshot of recent advertising.
The study says that from Oct. 21-28, $38 million in ads were run and the Obama campaign had nearly triple the spending of the McCain campaign, $21.5 million to $7.5 million. Another $6.7 million in spending from the Republican National Committee on behalf of Mr. McCain lessened some of Mr. Obama's advantage. All of the party ads were negative.
Another $2.2 million was spent by interest groups.
As expected, most of the spending was in battleground states, but the study said more than three quarters was spent in states President George Bush won four years ago.
It also said that while the Obama campaign outspent the McCain team and Republicans nearly 3 to 2 overall, there were some states where the margin was far higher.
In Nevada, Mr. Obama outspent Mr. McCain and the RNC over 2 to 1; in Minnesota Mr. Obama's margin was nearly 3 to 1. In Wisconsin, Mr. Obama outspent Mr. McCain and the RNC by a margin of over 5 to 1. Mr. McCain and the Republican Party outspent Mr. Obama only in North Carolina and Iowa.
Florida stations were the biggest beneficiary, with $6 million of the total spending going to that state's stations. Pennsylvania was second.
The study also said that the Obama campaign is on track to spend a record $100 million on broadcast TV in October.
Ken Goldstein, a professor at the University of Wisconsin and director of the project, said the heavy spending this year by the Obama campaign is rewriting the rules.
"Political scientists usually think that presidential races are poor places to find advertising effects because both campaigns typically have similar resources and air ads in similar markets," he said. "The advertising advantage held by the Obama campaign this year puts us in uncharted waters. This year the spending is hugely unequal and in some cases, the Obama campaign has massive advantages."