During half-time, the car manufacturer broadcast a two-minute advert that didn’t focus on cars.

Instead, Eastwood’s gravelly voice announced to the country that it was “half-time in America too”.

He added: “People are out of work and they’re hurting. They’re all wondering what they’re going to do to make a comeback. And we’re all scared because this isn’t a game.

“This country can’t be knocked out with one punch. We get right back up again and, when we do, the world is going to hear the roar of our engines.”

The advert focused on Detroit, where Chrysler is based, and looked at how people are getting back on their feet after the recession.

It included only passing references to car brands and instead focused on conveying a patriotic message of hope during en economic downturn.

The half-time period during the Super Bowl attract as much as $3.5 million (£2.2 million) from companies wanting to advertise for 30 seconds.

Dr Bill Nichols, public relations expert at Buckinghamshire New University, said it was a bold step for the car company: “It is so ambitious on a number of dimensions. It is really rare for people to go for that kind of social level and go for it so convincingly over such an extended format.”

Republicans have claimed it was a nod to President Obama, who bailed out the auto industry during the recession.

Eastwood, 81, has defended the advert, insisting it wasn’t a political endorsement.

He said: “I am certainly not politically affiliated with Mr Obama,

“It was meant to be a message about just about job growth and the spirit of America. I think all politicians will agree with it.”

Watch Clint Eastwood’s Chrysler advert: