At the white house yesterday, President Obama continued his push for the “Buffet Rule.” That’s a proposal he says would require the very wealthy to pay the same tax rate as the middle class. The senate is slated to vote on the buffet rule next week. Everyone agrees it’s not likely to pass. The Obama campaign says tax fairness will be a central theme in the 2012 election. But congressional republicans call the measure a political gimmick. And advisers to GOP front-runner Mitt Romney say the president is just trying to divert attention from his economic record. As tax day approaches, a look at the fiscal impact and political implications of the debate over taxes.