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This graph shows the weekly spending on TV ads for the presidential campaign by the Republican candidates and president Obama up until April 2012. Only those candidates still campaigning for the elections are depicted here. Mitt Romneys spending on TV ads increased between January 16 to 22, to 1.8 million U.S. dollars. Barack Obama started spending money on TV ads in that week, spending about 0.513 million U.S. dollars.