“The ad wars” is an election series Wonkblog is running in which George Washington University political scientist (and Monkey Cage founder) John Sides shows you what’s really happening on the airwaves.

The Washington Post’s advertising data has now been updated through Nov. 4, and  shows that an already intense flow of advertising to battleground states became even more so.  All told, more than 120,000 ads aired between Oct. 28 and Nov. 4, nearly double what was aired Oct. 21-27.

The final push from the Romney campaign and its allies is evident.  For the first time this fall, they aired more ads than did the Obama campaign and its allies—about 7,500 more.

As was true in the previous week, this week’s massive spike in Republican spending was driven largely by super-PACs.  The Obama campaign also increased its advertising, but not by enough to match Romney and the Republican super-PACs combined.

The trend in the battleground states reveals a strong push by the GOP nearly across the board—including Florida, Nevada, Iowa, and especially Pennsylvania. This confirms much of the reporting about the renewed Republican interest in Pennsylvania.  Both Romney and Republican super-PACs increased their spending in the Keystone State last week.  Note also that the Democrats closed the previous week’s gap in Ohio.  Last week, the two sides were nearly at parity there.

During this period from Oct. 28 to Nov. 4, here is the balance of spending in the battleground states.

On balance, the GOP had an advantage in many of the closest states—Iowa, Florida and Ohio.  Its advantage in Pennsylvania also is clear.

In closing, I’ll repeat what I’ve said in nearly every one of my posts on the ads. Because the effects of ads decay quickly, this last week’s advertising may be more important than anything that aired even as recently as mid-October.  But did either party get enough of an advantage for the advertisements to do more than cancel each other out?  After tomorrow, we can begin to answer this question.