Protestantism is far more varied than Roman Catholicism. Liberal Protestants are quite likely to vote for the Democratic Party in the United States. In the United States Bible Belt fundamentalist protestant vothers are overwhelmingly Republican.
Protestant leaders have been known to advise members how to vote. In the 2008 elections the Democratic party has to counter suggestions that those who vote Democrat can go to Hell for it. All Christians believe that God is omniscient and knows what voters do in the secret of the voting booth. When religious leaders tell the faithful how to vote this weakens the secret ballot and undermines democracy.