In a recent debate, Delaware Senate candidates Chris Coons and Christine O'Donnell discussed the separation of church and state and the First Amendment. The Washington Post reports:

Republican Senate nominee Christine O'Donnell of Delaware on Tuesday questioned whether the U.S. Constitution calls for a separation of church and state, appearing to disagree or not know that the First Amendment bars the government from establishing religion. 

Coons said private and parochial schools are free to teach creationism but that "religious doctrine doesn't belong in our public schools."

"Where in the Constitution is the separation of church and state?" O'Donnell asked him.

When Coons responded that the First Amendment bars Congress from making laws respecting the establishment of religion, O'Donnell asked: "You're telling me that's in the First Amendment?"

Her comments, in a debate aired on radio station WDEL, generated a buzz in the audience.

You can watch video of the exchange at the link above. The mistaken notion that the separation of church and state is not in the US Constitution is one of the top ten "lies about church and state" debunked by Brent Walker here.