Prime Minister Julia Gillard faces a long night of pressure to lift Australia\'s ban on gay marriage after a left-leaning lobby group won an annual auction for an evening of her time. Political activists GetUp! bid Aus$31,100 (US$32,855) for the dinner for six, raffled at a media charity ball on Wednesday night, and said three same-sex couples would use it to ask her why they could not wed. Gillard is personally against gay marriage and both her ruling Labor party and the conservative opposition support Australia\'s current ban, despite polls suggesting growing public support for the law to change. The left-wing Greens, a key partner in Gillard\'s minority coalition government, want a vote on the issue, and lawmakers agreed last November to gauge views in their electorates and report back to parliament. \"The face-to-face time with the PM was billed as a \'unique opportunity for corporate Australia\',\" said GetUp! director Simon Sheikh. \"But rather than dining with executives and business leaders, Julia Gillard will be forced to make the case as to why these couples cannot have their relationships recognised in the same way other Australians do.\" Funded by public donations, GetUp! also won a meal with independent MPs Tony Windsor, Rob Oakeshott and Bob Katter, the so-called \"kingmakers\" who hold the balance of power in the lower house and delivered power to Gillard. Three prominent gay rights campaigners will put their views to the men as they dine, Sheikh said, an opportunity that cost Aus$12,100. \"During the federal election a year ago, it became evident that marriage equality was an issue Australians cared about despite the major parties\' failure to address it,\" he said. \"Our politicians are elected to lead, but are far behind the public on this. It\'s time they step up to the plate and support equality and fairness for all couples.\" It is the second time GetUp! has won the annual raffle, last year securing a surfing lesson with right-leaning opposition leader Tony Abbott for an Afghan refugee in a bid to shift Abbott\'s tough stance on boatpeople.