New York, Jan 6 (IANS): Talking directly or subtly about religion during campaigns can increase a candidate's chances of winning an election as voters tend to trust such candidates more than atheists, says a new study.

"Their religious identification reflects a powerful, widespread, but often subtle and unconscious bias in American society against those who do not believe in God," said one of the researchers Scott Clifford from University of Houston in the US.

The study noted that there has been only one openly atheist congressman (Pete Stark from California), who lost in 2012.

Using national survey polling data, the researchers assessed the willingness of voters to support an atheist candidate, the favorability of candidate Hillary Clinton depending on whether she is viewed as religious, and the view that a religious candidate is trustworthy.

The analysis revealed that almost a third of the respondents said atheists cannot be moral.

"Our findings suggest that not demonstrating religiousness is a significant roadblock for winning public office in the United States, and being perceived as religious increases the level of trust instilled in politicians by voters," Clifford said.

"For Republicans (showing religiousness) will reinforce their existing support, but Democrats can expand appeal to moderates and conservatives with displays of religiousness," Clifford noted.

The findings were published in the journal American Politics Research.