President Obama's campaign manager said Tuesday that an ad suggesting Jeep was moving production to China was the biggest mistake made by Mitt Romney's campaign.

"They ended up spending the last 14 days of the election in the Midwest on the defense," Messina said at a Politico Playbook breakfast. The ad was criticized by factcheckers and by major car companies. 

Messina said that one of the best decisions made by the Obama campaign was to hire non-political tech staff -- advice he got from Google chairman Eric Schmidt.

If you asked Harper Reed, the campaign's chief technology officer, what the campaign did, Messina said, he would say, "They just built a whole bunch of things to make door knocking easier."

Some of those tools -- in particular, the social Dashboard -- will be used to pressure lawmakers on a fiscal cliff deal, Messina suggested. 

"People want to be involved in supporting the president’s agenda in the next four years," he said. Supporters were asked in a recent email how they would "like to stay involved in the future."  That's a shift from 2008, when Obama shut down his network after the election.

Messina, who worked in the administration from 2009 to 2011, said he too will likely be working from the outside this term. 

"I think my future is probably outside the White House," helping advocate for Obama's agenda, he said. A decision on his future role will be made by the inauguration, Messina said. To start, he's taking a vacation for the first time in five years. "The president and I were joking recently about how bad I look," he said.