In the clip, Hannity acknowledges that he needs to read from a script before beginning the interview.
ROMNEY: "Oh you have a prompter, okay. Where's my prompter, that's what I want."

HANNITY: "You don't use one. I think Obama sleeps with his."

ROMNEY: "Every event he did - it does make some sense though, I understand, it makes some sense."

HANNITY: "Yeah, of course it does."

ROMNEY: "Because, you know, it keeps you from saying something you don't mean, you get the message out precisely the way you want to get it out."

HANNITY: "Did you use a prompter the other night, I didn't know if you did?"

ROMNEY: "I did. The times I use prompters, maybe five times so far in the campaign — major speeches."

HANNITY: "That's smart. You're right, you don't want to make a mistake. I'll tell you, they're out to just eviscerate anyone who makes a mistake."

Romney has begun using the devices more frequently in recent appearances as his grasp on the Republican nomination has become increasingly firm.

But in doing so, he may undermine one of the GOP's favorite attack lines. Hannity has mocked the president's use of teleprompters hundreds of times on his radio and television shows, and GOP presidential candidates often mocked the tool on the stump.

Rick Santorum said last month in Louisiana that "when you run for president of the United States, it should be illegal to read off a teleprompter, because all you're doing is reading someone else's words to people."

And Newt Gingrich, who technically remains in the hunt for the Republican nomination, frequently jokes about challenging the president to Lincoln-Douglas style debates and allowing the president to use a prompter at them.

"I already said that if he wants to use a teleprompter, then it would be fine with me. It has to be fair. If you [were] to defend ObamaCare, wouldn't you want a teleprompter?" Gingrich said while campaigning in Florida.