Point out that as talented as Obama is, he is still young, uppity, and not Episcopalian. The base will know what you mean.
Throw a bunch of veiled racist rhetoric at Obama, then argue that it is just regular campaign criticism, you would use against anyone. After all Obama is Black, you are being called a racist only because he is different. Again, you are the victim.
Highlight Obama’s odd name while confusing it with terrorists names, thus equating Obama with terrorists. The goal will be to peel off some ignorant voters who don’t know anyone not named john, paul, or joe.
Point out Obama’s non-American father. Throw anything you can against the wall. See if you can peel off some voters who have never been out of the United States. See if you can push the thought that he will be less loyal to America because he knows people in other places and some of them are family.
Find some way to question Obama’s patriotism. The goal is to cast doubt about who Obama will be working for as president, us or the foreigners in his family. You can do this by showing him being liked by people in other countries. If they like him then he must not be a true American.
Go after Obama’s wife. She is smart and outspoken. Paint her as a powerful woman who will have undue influence on a president.
Highlight Obama’s family upbringing. After all how can a man not raised by his natural father be a stable president.
Find something sexual or racist in Obama’s past. For example did he ever date a white woman? If he did, then highlight that a lot. Some voters, that would vote for a black man, would change their minds if he ever dated a white woman.
Show how the minorities, poor and young people love Obama. People don’t trust a man who’s base is not rich, white, old people. If he is liked by the poor, non-white, and young, then there is something to be worried about.
Make stuff up as needed. Anyone named Barak Obama, instead of John Smith, is worthy of doubt.
The overall theme must be to focus on Obama’s “otherness.” Someone so unique must be untrustworthy. He is black so not like most Americans. He was raised, in part, outside the country so not like most Americans. He has a weird name, so is not like most Americans.
If you have no shame, and no moral foundation, you will be willing to focus the public on how he is somehow not like "us" and thus can’t be trusted.