This report (PDF) asked citizens of various European countries to respond to statements about marriage and homosexuality. Here's what they said:
"It is a good thing to allow marriages between two men and two women"
Accept the statement as true - Poland: 11.8%, Hungary: 30.7%, Italy: 35.9%, Portugal: 37.6% France: 47.3%, Great Britain: 57.9%, Germany: 60.3%, The Netherlands: 83.0%
"There is nothing immoral about homosexuality"
Accept the statement as true - Poland: 24.2%, Hungary: 32.3%, Portugal: 56.0%, Italy: 57.5%, Germany: 62.0% Great Britain: 62.8%, France: 63.8%, The Netherlands: 83.5%
Here's the chart, which presents the same information as above, but asks if people reject (as opposed to accept) the statement as true: