It's President Barack Obama's birthday today, but according to a new poll, millions of Americans still refuse to believe he was born in the US:

According to a CNN/Opinion Research Corporation survey, more than a quarter of the public have doubts about Obama's citizenship, with 11 percent saying Obama was definitely not born in the United States and another 16 percent saying the president was probably not born in the country. ...

On Tuesday, conservative radio talk show host Rush Limbaugh quipped on his program, "They tell us August 4th is the birthday. We haven't seen any proof of that!"

We haven't seen any proof! None!