CNN

Former Republican congressman Bob Barr is running as a Libertarian candidate for president.

Republicans have something else to worry about besides the war in Iraq, the economy and President Bush. Former Republican congressman Bob Barr is running as a Libertarian candidate for president. Some in the GOP are worried Barr's candidacy will take away conservative votes from John McCain.

They fear that the Barr factor combined with high turnout and enthusiasm among the Democratic base could spell trouble for McCain. One Republican says he doesn't think Barr would get more than 4 percent of the vote... but that might be enough in some states.

And some Democrats agree... saying that Republicans are crazy if they aren't worried about Barr – who was the first lawmaker to call for Bill Clinton's resignation over the Monica Lewinsky scandal. He also made a name for himself fighting against the loosening of drug laws and supporting gun rights. The Libertarian Party is already on the ballot in 30 states – and is aiming for the other 20.

Not everyone is worried though.

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