In one study, we presented liberals and conservatives with one of two messages in support of same-sex marriage. One message emphasized the need for equal rights for same-sex couples. This is the sort of fairness-based message that liberals typically advance for same-sex marriage. It is framed in terms of a value — equality — that research has shown resonates more strongly among liberals than conservatives. The other message was designed to appeal to values of patriotism and group loyalty, which have been shown to resonate more with conservatives. (It argued that “same-sex couples are proud and patriotic Americans” who “contribute to the American economy and society.”)
Liberals showed the same support for same-sex marriage regardless of which message they encountered. But conservatives supported same-sex marriage significantly more if they read the patriotism message rather than the fairness one.
.. Despite the financial incentive, just 9 percent of liberals made arguments that appealed to more conservative notions of morality, while 69 percent made arguments based on more liberal values.