Underwood, who is a strongly believing Christian herself, spoke to the British newspaper the Independent about why she endorses marriage equality.
"As a married person myself, I don’t know what it’s like to be told I can’t marry somebody I love, and want to marry," Underwood said. "I can’t imagine how that must feel. I definitely think we should all have the right to love, and love publicly, the people that we want to love."
The 29-year-old "American Idol" winner also told the publication that she was brought up as a Baptist but now goes to a non-denominational church with her husband, Mike Fisher, a hockey player.
"Our church is gay friendly," the "Jesus, Take the Wheel" singer said. "Above all, God wanted us to love others. It’s not about setting rules, or [saying] ’everyone has to be like me’. No. We’re all different. That’s what makes us special. We have to love each other and get on with each other. It’s not up to me to judge anybody."
Many fans that don’t share the same views as Underwood have turned their backs on the country star, however. Some have taken to social media to attack the star, Gay Star News notes.
"I warned @carrieunderwood fans that their idol was going to get backlash for her support of marriage perversion and I was right! #asusual," one person tweeted.
"@carrieunderwood Is a disgrace. Being vegan and supporting gay marriage doesn’t seem very country at all," another said.
"Another day, and a another ’gospel’ artist signed to ’EMI’ comes out supporting gay marriage.@carrieunderwood Unequally signed to the devil," someone wrote.
GLAAD also launched a Twitter campaign in order to support Underwood. The organization wants supporters to tweet words of encouragement to the singer with the hash tag #supportcarrie.
Not only did fans slam the country singer for her pro-gay stance but also a pastor from Franklin, Tenn. did, as Crushable.com points out. Scotty Smith, the pastor of Franklin’s Christ Community Church, talked about Underwood’s statements on the Christian Broadcasting Network.
"What she said in that interview, unfortunately, has increasingly become a pretty broken understanding of what the Bible is saying. You want to listen to the Scripture in terms of what it says about everything, including marriage, including sexuality."
When the ultra conservative websites Life Site News and Free Republic reported the story swarms of readers voiced their disapproval of Underwood’s support for same-sex marriage.
"Using Christianity to defend and promote homosexuality is insulting. Ugh," someone said. "Being Saved doesn’t stop you from being dumb," another wrote. "Jesus just let go of the wheel," a commenter said.
The LA Times reports, however, that the singer is getting praise from one conservative group - GOProud, an organization for gay Republicans.
"Good for her," said Jimmy LaSalvia, co-founder and executive director of GOProud. "You know, Carrie Underwood isn’t any different from anyone else in America," LaSalvia said in an email to the Times. "The more Americans think about how issues affect their gay friends and family the more they come to realize that supporting same-sex civil marriage is the right thing to do. More and more people are coming to that conclusion - and that includes conservative Christians."
Going against the down-home grain usually doesn’t play well with country music fans. In 2003, the Dixie Chicks faced boycotts after a member criticized President George W. Bush and the invasion of Iraq in a concert.
Popular country star Chely Wright made headlines as well as some enemies when she came out as a lesbian in 2010. Wright is the first major country singer to publically come out as gay, which many conservative fans of the genre saw as an issue. Last year a documentary called "Wish Me Away" chronicled Wright’s coming out story and her role as a gay rights activist.