Santorum says he believes in religious freedom, but constantly advocates for religious laws that limit the freedom of other (non christian) religions.
Gingrich left the house on ethics charges. He was also leading the impeachment of Clinton for having an affair, while he was cheating on his wife. Newt also routinely calls Obama a socialist. However Newt recently called for a US moon base, which would undoubtably be paid for by government spending. In addition he wants their to be orbital commercial activity and private sector space trips. If Newt is serious, then he would have to "assist" private companies in becoming equipped for space travel.
Romney also believes (maybe) "the banks" are hurting under the burden of Obama's socialist regulations. Romney wants (maybe) to deregulate banks, which for anyone who has knowledge about the tragedy of Fannie Mae and Freddy Mac realizes that this is what caused our current financial crisis.
Obama is definitely not perfect, but he is not an embarrassment.