What Does It Mean to Be Mormon?

Dec. 6, 2007 — -- There are 6 million Mormons living in America, and Mormonism is one of the fastest-growing religions on the planet, with more than 12 million believers worldwide.

Later today Republican presidential contender Mitt Romney will make a speech publicly defending his Mormon faith. This morning, in anticipation of the former Massachusetts governor's speech, ABC News correspondent Dan Harris answered some common questions on "Good Morning America" about what it means to be Mormon.

"When we went to an official church event recently, we were asked to sign this paper promising not to smoke or drink on church premises," said Harris.

The Mormon church has gone through an extraordinary transformation since its early days as a renegade religion. Today, it is very much in the mainstream. The Mormon Tabernacle Choir performs at presidential inaugurations. There are 10 Mormons in Congress and plenty of Mormon celebrities, including Gladys Knight and Donnie and Marie Osmond.