The tweet included a link to Obama's campaign website inviting followers to sign up. 

Ann Romney, who appeared on multiple networks Friday morning to discuss the previous night's convention speeches, dismissed questions about Eastwood's speech, which some have called a distraction from the campaign.

"I didn't even know he was going to come on stage," she admitted to ABC's "Good Morning America."

She told NBC's "Today" show she doubted if anyone could plan what Eastwood would do on stage.

"We were just thrilled, frankly I was thrilled, for his support," she said.