GOP 2016 contenders: Who's in, who's out at CPAC

This week, at the Conservative Political Action Conference (CPAC) in Washington, D.C., some of the Republican Party's top potential presidential candidates will test their rhetorical skills -- and possible future platforms -- before some of the nation's most dedicated conservatives. But while the high-profile convention could be a great showcase for politicians like Sen. Rand Paul, R-Ky., and Sen. Marco Rubio, R-Fla., there are a few notable omissions from the lineup. Here's a look at who's on the roster - in order of appearance - and who won't be showing up.

Credit: CBS