
When it comes to remaining faithful in a marriage, attitude can be everything.

Nearly three quarters (74 percent) of Americans believe it is 'always wrong' to have sex outside of marriage, according to the General Social Survey.

But that leaves 26 percent who think it is rarely, sometimes or always acceptable to stray outside of marriage.

A DailyMail.com analysis of the GSS - which is a comprehensive survey that has tracked American attitudes and beliefs since 1972 - breaks out which groups are more flexible when it comes to extramarital sex, finding that Democrats, white Americans and rich people are more likely to think cheating is sometimes acceptable.

Just 65 percent of Democrats believe it is always wrong to cheat, compared to 86.5 percent of Republicans, according to the General Social Survey

This chart illustrates the share of each political party believes it is always, almost always, sometimes and never wrong to cheat on a spouse

For example, just 65 percent of Democrats believe it is always wrong to cheat, compared to 86.5 percent of Republicans.

To break it down further, 19 percent of Democrats say it's 'almost always wrong' to have sex outside of marriage, while 12 percent believe it's sometimes wrong and 3 percent said it's not wrong at all.

By comparison, 8 percent of Republicans say it's 'almost always wrong,' 4 percent say it's sometimes wrong and 1 percent believe it's not wrong at all.

In addition, nearly three quarters (73.2 percent) of independents believe being unfaithful is always wrong.

'Democrats are more liberal in general - and less religiously based - hence more liberal about personal peccadillos and sexual trespass – not that they approve,' said Pepper Schwartz, a sociologist and sexologist at the University of Washington.

Interestingly, the share of Democrats who say cheating is always wrong has declined since a peak of 82 percent in 2008 - which Schwartz told DailyMail.com could have something to do with the economic downturn that started that year.

'From 2007 to 2011 we had turbulent economic times, and I believe that was a big stressor across the board for people,' she said. 'A lot of people were faced with tumultuous economic decisions which are never good for relationships.'

Meanwhile Republicans have seen a steady rise since 1973 in the share whom believe it's always wrong to cheat.

'They’re much more churched,' Schwartz said of the uptick among Republicans. 'Their beliefs are that much more under threat.'

Clarissa Silva, a behavioral scientist and researcher who has studied sexual behavior, notes that beliefs may not always be consistent with actions.

'In general, the more politically conservative an American is the more restrictive their public persona on sexual attitudes will be,' she told DailyMail.com.

'However, these differences in attitudes don't always correlate to differences in actions,' she added. 'Studies have found that Republicans cheat more often and are more sexually deviant in their practices than their more liberal peers.'

Attitudes are separate from the reality of stepping out on a spouse: just 15 percent of married women and 25 percent of married men have cheated on a spouse, according to the American Association for Marriage and Family Therapy. Those numbers rise by about 20 points when emotional and sexual relationships without intercourse are factored in.

More than 81 percent of black Americans say it is always wrong to cheat on a spouse, compared to less than 73 percent of white Americans

The differences also split along racial lines, with African Americans less likely than white Americans to be comfortable with the idea of sex outside of marriage.

More than 81 percent of black Americans say it is always wrong to cheat on a spouse, compared to less than 73 percent of white Americans.

Among white people, 16 percent said it's 'almost always wrong' to stray outside of marriage, while 8 percent said it was sometimes wrong and 1 percent said it was not wrong at all.

Among African Americans, 10 percent said it was 'almost always wrong,' while 8 percent said it was sometimes wrong and 1 percent said it was not wrong at all.

Schwartz noted that African Americans are much more likely to regularly attend church and be committed to a religion than their white counterparts – which could be a factor in how they answered the questions.

Silva, however, said that the reality could be different from survey responses.

'Several studies have found that African American men cheat more than white men,' she said. 'One possible explanation of this dichotomy (between survey data and those findings) is the racial differences in self-perception and locus of control.'

'White men tend to attribute their life circumstances and subsequent decision making to an internal locus of control, the belief that they are responsible for driving their own success, whereas black men feel that their outcomes are attributable to an external locus of control, the belief that external forces determine their outcomes,' she added.

Attitudes also break along educational lines, with the more educated survey respondents more comfortable with the idea of cheating in some situations

Less than 66 percent of the upper class believes it is always wrong to cheat on a spouse, while the 83.3 percent of the poorest Americans feel that way – a more than 23 point spread between the classes

Attitudes also break along educational lines, with the more educated survey respondents more comfortable with the idea of cheating in some situations: 79.6 percent each of those with just a high school degree and those who didn't finish high school believe cheating is always wrong.

That's compared to 65 percent of those with a college degree or higher – a near 15 point difference.

An additional 20 percent of college grads said that cheating is 'almost always wrong,' while 13 percent said it is sometimes wrong and 1 percent said it was not wrong at all.

In a related finding (given the widely accepted link between education level and lifelong earning potential), wealthy Americans are more likely to think cheating is sometimes acceptable.

Less than 66 percent of the upper class believes it is always wrong to cheat on a spouse, while 83.3 percent of the poorest Americans feel that way – a more than 23 point spread between the classes.

The upper class has actually rebounded since 2014, when just 47 percent said it was 'always wrong' to cheat.

'Upper and middle-class Americans tend to use a cost-benefit calculation when deciding whether to have an affair or not,' Silva said. 'This calculation is determined by biological and socioeconomic factors and varies based on gender.'

'Younger and lower-income women cheat to improve their genetic pool or to enhance the outcomes for their current children,' she added. 'Upper and middle-class American men calculate the risk of being caught by divorce settlement risk.'

Some 79 percent of Southerners believe cheating is always wrong – the biggest share in the country – while 73 percent of those in the Midwest, 72.7 percent in the West and just 63 percent in the Northeast share that belief

The survey also reveals regional differences in attitudes about cheating: Southerners are the least likely to believe it's acceptable, while Americans living in the Northeast have the most lax ideas about extramarital sex.

Some 79 percent of Southerners believe cheating is always wrong – the biggest share in the country – while 73 percent of those in the Midwest, 72.7 percent in the West and just 63 percent in the Northeast share that belief.

Schwartz noted that one factor could be that the Southern U.S. is more church based and has higher church attendance – though it's unclear if their actions are consistent with their beliefs.

'These red states have higher divorces than the blue states - and most southern states are red,' she said.

The share of Americans who believe it's always wrong has declined in all four regions of the country since 2014.

Perhaps least surprising was that men are more likely than women to think cheating is acceptable sometimes. Some 78 percent of women think it's always wrong to stray from a marriage, compared to nearly 69 percent of men – a 9 point difference in attitudes.

Silva said the gender findings were a 'good predictor' of actual cheating behavior.

'Several studies show that men do cheat more often than women although the number has increased more for women in the past decade,' she said. 'Some of the leading reasons women cheat are feeling loneliness, sexual dissatisfaction or deprivation ... or from the lack of orgasms and intimacy with their spouse.'

'Leading reasons men cheat differ: insecurity, ego validation, immaturity, inability to terminate the marriage or inability to be alone, impulsivity and misdirected anger that blames his failure on his wife,' she added.