Oh, how the mighty Libertarian has fallen. When Rand Paul held his filibuster, the media, RNC and many in the conservarazzi were joyous. Not only did he take a principled stand, they said, but he also had the supporter of his Dad's followers by his side to win straw polls and raise tons of cash off of. He seemed like a top tier 2016 presidential candidate. Unfortunately, that hasn't happened so far. In fact, he's fallen so far that his campaign produced a Donald Trump attack ad.

Sen. Rand Paul (R-Kentucky) is taking his criticism of GOP presidential rival Donald Trump to the next level.

Paul's campaign released an online attack ad against Trump on Wednesday that blasts him for past statements praising Democrats and left-leaning policies.

"In many cases I probably identify more as a Democrat," Trump says in a clip from a 2004 interview featured in Paul's ad. "I've been around for a long time and it just seems that the economy does better under the Democrats than the Republicans."

In another part of the ad, Trump declares that now-Democratic presidential candidate Hillary Clinton is a "terrific woman."

"I'm a little biased because I've known her for years. I live in New York, she lives in New York, and I've known her and her husband for years. And I really like them both a lot," Trump says in the clip.

Paul's campaign said the ad is online-only and "will run through the weekend in Iowa and New Hampshire."

Attacking Trump hasn't been fruitful for any candidate so far, including Rick Perry, so I'm not sure why Paul's campaign thought this was a good idea. It's probably more the fact that he's slipping into the second tier of candidates and feel pressured to try something, anything, to get the poll numbers up. It won't work.

As usual Trump responded. Donald Trump mocks Rand Paul, calls on him to quit presidential race

Donald Trump sent The Washington Post a lengthy response to Kentucky Sen. Rand Paul's ad. Here it is, in full.

Rand Paul is doing so poorly in the polls he has to revert to old footage of me discussing positions I no longer hold. As a world-class businessman, who built one of the great companies with some of the most iconic real estate assets in the world, it was my obligation to my family, my company, my employees and myself to maintain a strong relationship with all politicians whether Republican or Democrat. I did that and I did that well.

Unless you are a piece of unyielding granite, over the years positions evolve as they have in my case. Ronald Reagan, as an example, was a Democrat with a liberal bent who became a conservative Republican.

Recently, Rand Paul called me and asked me to play golf. I easily beat him on the golf course and will even more easily beat him now, in the world in the politics.

Senator Paul does not mention that after trouncing him in golf I made a significant donation to the eye center with which he is affiliated.

I feel sorry for the great people of Kentucky who are being used as a back up to Senator Paul’s hopeless attempt to become President of the United States--- weak on the military, Israel, the Vets and many other issues. Senator Paul has no chance of wining the nomination and the people of Kentucky should not allow him the privilege of remaining their Senator. Rand should save his lobbyist’s and special interest money and just go quietly home.

Rand’s campaign is a total mess, and as a matter of fact, I didn’t know he had anybody left in his campaign to make commercials who are not currently under indictment!