A disagreement between House Democratic leaders over Obamacare subsidies spilled into the open Tuesday, threatening to undermine their negotiating position as they hash out a deal with Republicans to fund the government.Democratic negotiators, led by House Minority Leader Nancy Pelosi (D-Calif.), are demanding the final funding bill include language to provide permanent Obamacare subsidies to help cover costs for low-income enrollees and keep insurance markets afloat.But House Minority Whip Steny Hoyer (D-Md.), No.