That "mystery speaker" listed on the schedule for the Republican National Convention taking place in Tampa, Florida right now may have just been revealed: According to a source for the GOP, none other than legendary filmmaker and actor Clint Eastwood is set to speak tonight, right before Senator Marco Rubio and Republican presidential candidate Mitt Romney. Nothing has been officially confirmed, but Fox News is backing this report up, so you can take that for what it's worth.

Earlier this month, Eastwood made his support of Romney's presidential campaign public at a fundraiser in Sun Valley, saying, "Now more than ever do we need Gov. Romney. I'm going to be voting for him," before adding that he hopes Romney will restore "a decent tax system that we need badly."

According to Deadline, amongst the others being speculated as the possible "mystery speaker" were Sarah Palin, Donald Trump, and "even a hologram of former President Ronald Reagan." Talk about an act to follow.

[via Deadline]