By Toby Harnden  and Hugo Gye PUBLISHED: 18:49 EST, 14 May 2012 | UPDATED: 02:47 EST, 15 May 2012 Barack Obama sought to make his newfound enthusiasm for gay marriage a campaign issue as he appeared on The View to defend his much-talked-about announcement. In an interview set to air tomorrow, the President told the hosts of the ABC daytime chat show that the controversial debate would be 'a big contrast in the campaign' against Republican Mitt Romney. Mr Obama announced, 'I think same-sex couples should be able to get married,' during another ABC interview last Wednesday. The historic declaration is intended to fire up liberal activists who consider gay marriage to be a hugely symbolic social issue.
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President appears on The View in interview to be aired on Tuesday
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Historic stance could threaten support from African-American churches
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Republicans urge campaigns to focus on the economy not social issues
Mr @placeholder opposes same-sex marriage but has been relatively silent on the issue over the last week, as senior Republicans have insisted the election should focus on economic rather than social issues.