There has not been a political advocacy organization which addresses the interests of Roman Catholics as Roman Catholics. We hope to keep the public square safe for Catholics. If that sounds alarmist, you should consider the frontal assault which is being waged politically against the Church in the United States. Below are a couple of articles which track some of the millions of dollars which are being spent to undermine the voice of the bishops, the traditional representatives of the Roman Catholic point of view.
Though they are a tiny minority, opinions to the contrary, nuns for homosexual marriages, Catholic women for abortion, priests for euthanasia, are given nearly unlimited resources to exaggerate their influence. It was the encouragement from dissident nuns which led to the political cover for the passage of Obamacare and its HHS Mandate attempting to force the Church to cooperate with abortion and contraceptives freely distributed (which is a redundancy since it is the failure of contraceptives which leads to most abortions!). Of particular interest is this article on the funding of wayward Catholic views on homosexuality by a couple of gay billionaires who run the Arcus Foundation and the Gill Foundation. For a detailed recap of the nefarious activities of these two foundations, see this article from Crisis Magazine. And appreciate that Catholics for Ohio is needed for the sake of the Church. More here: http://www.crisismagazine.com/2014/marginalizing-magisterium-one-grant-time