Conservatives received a blunt word of caution from an unlikely source about their conduct at this week's annual CPAC convention.

Right-leaning Fox News anchor Bill O'Reilly said the conservative movement would be "making a big mistake" if it spends the weekend "bashing Obama."

Convention speeches throughout Thursday were rife with forceful attacks on Obama, including substantive complaints as well as many purely personal jabs.

"What has bound them together so far is President Obama," O'Reilly noted Thursday night, playing clips of speakers such as former vice president Dick Cheney, Sen. Jim DeMint (R-SC) and former governor Mitt Romney throwing provocative punches and jokes at the president.

O'Reilly then asked grimly, "Does Obama bashing accomplish anything?" He said that while policy criticisms are fine, "the personal stuff is cheap, and we're seeing more and more of it."

"[I]f CPAC makes a weekend out of bashing Obama," O'Reilly said, "it will be making a big mistake. In order to regain power in America, conservatives must come up with solutions to complicated problems. And that's what they should be doing at the Washington convention."

O'Reilly made it a point to note that he also criticized liberals for "personal attacks" on President Bush that were "vicious and accomplished nothing."

An early speaker on Thursday, Young America Foundation spokesman Jason Mattera, explicitly said Obama's "notion of freedom" is "snorting cocaine."

And more punches were thrown on Friday.

Speeches on Friday morning by two high-profile Republicans, Minnesota Gov. Tim Pawlenty and Rep. Mike Pence (R-IN) -- both rumored to be potential 2012 presidential contenders -- included a series of aggressive criticisms of President Obama's policies and character.

"If government spending were an Olympic sport, [Obama] would be a repeat gold medalist," Pawlenty declared.

Rep. Steve King (R-IA) said of Obama's health care bill, "I don't want to meet with the president of the United States to see what other kind of toxic stew he is going to serve to us."