How should I respond to friends who fanatically hate President Obama?

As a free-market advocate, I'm distressed about President Obama's policies. However, I'm increasingly worried about some of my friends in the free-market movement exhibiting an alarming level of hatred for President Obama. I have seen my friends latch on to every "juicy"-sounding accusation against the President, which they spread all over Facebook, such as spurious claims that the administration violently threatened Bob Woodward, or that the President conspires to grant himself a third term. I think a reasonable discourse on Obama's faults is necessary, but the conspiracy theories and outright hatred cloud people's judgments. I want to ask my pro-free-market, Obama-hating friends that they not bring up their dubious accusations in conversation, but I don't know how to do that without offending them. Is there a solution to this dilemma?