Presidential primary thorn Ron Paul (R-Have I Pricked You Now?) has turned his advertising sights on GOP frontrunner Rick Perry (R-Prick This).

Paul’s latest ad (and, credit where credit’s due, he’s the only Republican candidate running a real on-TV – v. Mitt Romney’s weak-ass web videos – advertising campaign) is, according to Politico, “[a] 60-second spot, backed by a six-figure ad buy — the first negative ad attacking Perry to come directly out of a Republican campaign this primary season — [that] contrasts Paul’s endorsement of Ronald Reagan in 1980 with Perry’s role as the Texas chairman for Gore’s first presidential campaign.”

Ouch.

Key text:

After Reagan, Sen. Al Gore ran for president, pledging to raise taxes and increase spending – pushing his liberal values. And Al Gore found a cheerleader in Texas named Rick Perry.

Rick Perry helped lead Al Gore’s campaign to undo the Reagan Revolution, fighting to elect Al Gore president of the United States.

Now America must decide who to trust – Al Gore’s Texas cheerleader, or The One [see Campaign Outsider here] who stood with Reagan.

Double-ouch.

This is Paul’s third six-figure ad buy in Iowa and New Hampshire. Coincidentally or not, he’s also running third in most national and early-primary-state polls.

Time to take this guy seriously?