Although US President Barack Obama has been in power for more than six years now, not a few Americans—in particular those who support the Republican Party—still do not know much about him, including his religion and where he was born.

Two separate surveys held this month showed that many Republicans believe Obama is a Muslim and that he was born outside the United States.

A CNN/ORC poll released on Sunday showed that 29 percent of Americans, and 43 percent of Republicans, believe Obama is a Muslim.

Last Sept. 1, a survey from the left-leaning Public Policy Polling (PPP) showed that an even bigger number of Republicans—54 percent—believe Obama is a Muslim.

The president is actually a Christian who was baptised into the United Church of Christ (UCC) denomination and formally joined it in 1988, based on records. He reportedly left the UCC in 2008 and has not become a formal member of any church since then.

But although Obama is a practicing Christian and was raised by his mother and her Christian parents, the president's father—Barack Obama, Sr., who lived with him only during his infancy—was reportedly a Muslim-turned-atheist. Moreover, Obama's stepfather Lolo Soetoro, who was with him during his early childhood years, was reportedly a nominal Muslim.

Some 39 percent of Americans were able to correctly identify Obama's religion, saying they believe he is either a Protestant or Christian. Another 11 percent said the president is not religious, while 14 percent had no opinion on the president's faith.

The CNN/ORC poll also showed that while majority of Americans believe, correctly, that Obama was born in the United States, some believe he is foreign-born. Nine percent of those polled believe that Obama was born elsewhere, while 11 percent just say they suspect he was not born in America. The president was born in Hawaii.

In 2010, an ABC News/Washington Post poll found similar numbers when asking about the President's birthplace, with 20 percent saying he was born outside the country, according to The Hill.

Since then, the president has produced a birth certificate proving definitively he was born in Hawaii.

In PPP's Sept. 1 survey, 32 percent said they were unsure of Obama's religion. Only14 percent said they believe he is a Christian.

Many right-leaning voters have been deeply sceptical about Obama's faith since he became president.

The topic rose prominently in 2012 when Obama faced former Massachusetts Gov. Mitt Romney, a devout Mormon, in the general election.

Obama rarely invokes his own faith in speeches and public appearances, though has remarked about his Christian faith during comments for holidays such as Easter.

A total of 1012 adults were interviewed by phone for the CNN/ORC poll, with 27 percent describing themselves as Democrats, 24 percent as Republicans, and 49 percent as independents or members of another party. The poll was conducted from Sept. 4 through Sept. 8.

The PPP survey obtained by MSNBC was conducted over the past week and has a margin of error of 4.1 points.