A new TV ad featuring former President Bill Clinton is the latest evidence of a deliberate and potentially risky advertising strategy by the Obama campaign to blitz airwaves with its strongest material months before the general election.

President Barack Obama's campaign is hoping to inoculate itself from what's expected to come: a barrage of commercials from Mitt Romney and Republican independent groups in the fall.

In Obama's latest ad, Clinton endorses the president and his economic policies. It's slated to air in eight battleground states, timed to run right before the Republican National Convention begins next week. The ad is the culmination of an approach Obama's team has followed since Romney became the all but certain GOP nominee in April. The Obama campaign's goal has been to present the former Massachusetts governor as an unacceptable alternative, despite the weak economic recovery and stubbornly high unemployment throughout the president's tenure.

"If you look at the ad pattern, the Obama campaign sees it as a 7-month run and the Romney campaign sees it as a 3-month sprint. Everything we're seeing points to that," Elizabeth Wilner, vice president for Kantar/Campaign Media Analysis Group, said. "It's a gamble for both sides, and whoever is right will win."

Ad spending is expected to hit $1.1 billion in the 2012 presidential contest. About one-third of that has already been spent, according to Kantar/CMAG, which tracks campaign ads.

The spending reflects the divergent ad strategies from the Obama and Romney teams. Obama's campaign has frontloaded its ads throughout the spring and summer, seeking to define Romney. The Romney campaign and groups affiliated with it have only recently caught up and exceeded the Obama campaign's spending. Romney and his allies are focusing the bulk of their advertising efforts on the weeks closer to the general election. They hope to capitalize on a successful convention and heightened interest from voters.

The Obama campaign's decision to roll out Clinton now, rather than closer to the election, reflects a calculation that his endorsement will carry more weight than when the airwaves are fully saturated.

"The Republican plan is to cut more taxes on upper-income people and go back to deregulation. That's what got us in trouble in the first place," Clinton says in the ad, set to air in New Hampshire, Virginia, North Carolina, Florida, Ohio, Iowa, Colorado and Nevada.

Obama, Clinton says, will help rebuild the middle class if re-elected. "That's what happened when I was president," Clinton says.

So far, Obama's campaign has spent $130 million on advertising, compared to about $70 million for Romney. But a trio of Republican-leaning outside groups has spent about $100 million on ads supporting Romney. That's allowed the candidate to remain competitive in ad spending and even exceed the Obama campaign in recent weeks. And when Romney officially becomes his party's nominee next week, he'll be free to spend millions more in money designated specifically for the general election.

Anticipating the ad spending disadvantage, the Obama campaign began its general election ad buys in mid-April.

A barrage of ads hitting Bain Capital, the venture firm where Romney made millions, was released in early May. The ads depicted Romney as a corporate raider who had bankrupted companies and laid-off workers — an effort to undermine his contention that his experience as a businessman makes him more qualified than Obama to fix the economy. A series of spots criticizing Romney's record as Massachusetts governor quickly followed.

A pro-Obama independent group, Priorities USA Action, was also on the air in the spring with ads slamming Romney's record at Bain. But the group has struggled to raise money and hasn't provided the level of help Romney is getting from allied independent groups.

Romney ceded much of the spring and early summer to those organizations — Restore Our Future, an independent group formed by former staffers, and to American Crossroads and Crossroads GPS, which are tied to former President George W. Bush's longtime political counselor Karl Rove. The groups have run ads hammering Obama on the economy, the stimulus plan and the health care overhaul.

Romney's campaign has ramped up more recently, airing ads that mostly criticize Obama rather than promoting the GOP presidential hopeful. Romney's campaign received a big assist earlier this month from Americans For Prosperity, an independent group backed by the billionaire brothers Charles and David Koch, which launched a $25 million ad campaign featuring voters who supported Obama in 2008 but plan to vote against him this time.

No state has seen more advertising than Ohio, where Obama and Republicans have spent nearly $100 million to date. Florida places a close second, while Virginia is third.

Wilner said that despite the Republican cash advantage going into the fall, the level of ad saturation in the battleground states thus far may make it difficult for Romney and his allies to gain significant new traction.

"For Obama, summer time may have proven to be a better time to get a message across than in the fall. Republicans are hoping sheer tonnage of ads will be enough to convince voters not to give another term," Wilner said.


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