Once again, Mississippi reigns as the most religious U.S. state, with 61 percent of its residents classified as "very religious," according to the results of a Gallup survey released Monday (Feb. 3).

In contrast, only 22 percent of people in Vermont ranked just as devout, and the Green Mountain state held onto its title as "least religious."

Overall, about 41 percent of Americans indicated that they are "very religious," meaning that religion is an important part of their daily lives and that they attend religious services every week or almost every week. Some 29 percent were classified as nonreligious, because they did not attend services and didn't cite religion as an important part of their daily life. Another 29 percent fell somewhere in the middle of the two extremes, and were labeled as "moderately religious."

For the most part, the rankings have remained largely unchanged since Gallup first started tracking religiosity in 2008. The most religious states still tend to be clustered in the South, though Utah — with its large population of Mormons, typically the most religious of any denomination — stands out as an exception and ranks No. 2 in religiosity, according to Gallup. Meanwhile, the least religious states are mostly found in New England, the Pacific Northwest and other states in the West.

Top 10 most religious states

Mississippi: 61 percent are very religious

Utah: 60 percent

Alabama: 57 percent

Louisiana: 56 percent

South Carolina: 54 percent

Tennessee: 54 percent

Georgia: 52 percent

Arkansas: 51 percent

North Carolina: 50 percent

Oklahoma: 49 percent

Kentucky: 49 percent

Top 10 least religious states

Vermont: 22 percent are very religious

New Hampshire: 24 percent

Maine: 24 percent

Massachusetts: 28 percent

Oregon: 31 percent

Nevada: 32 percent

Washington: 32 percent

Connecticut: 32 percent

Hawaii: 32 percent

District of Columbia: 32 percent

[See the full list of the most and least religious U.S. states]

Gallup officials said cultural differences and the geographic spread of different religions could explain the state-level variations in religiousness revealed in the poll.

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Protestants, for examples, have "above-average religiousness," according to Gallup, and the Southern states have a higher percentage of Protestants than the rest of the nation. In contrast, states in New England have a higher percentage of those with no religious identity at all.

In some states, there seems to be a strong cultural predisposition to be religious. According to Gallup, Protestants in Mississippi are more religious than Protestants in Vermont, and even those who don't identify with any organized religion in Mississippi are still more religious than Vermonters with no religious identity.

The rankings are based on more than 174,000 phone interviews conducted nationwide throughout 2013 as part of the Gallup Daily tracking survey. The results were weighted to be representative of each state's adult population by gender, age, race, Hispanic ethnicity and education, based on Census data, Gallup officials said.

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