WASHINGTON ( TheStreet) -- On the eve of a critical vote on the health care reform legislation that has been a primary focus of his administration, President Obama Saturday made a final appeal to House Democrats."Is this the single most important step that we have taken on health care since Medicare?" Obama was quoted asking rank-and-file Democrats by the AP. "Absolutely. Is this the most important piece of domestic legislation, in terms of giving a break to hard working, middle-class families out there since Medicare? Absolutely." Senate Majority Leader Harry Reid (D., Nev.) joined President Obama and House leaders and brought along a pledge from more than 50 other Democratic senators to quickly finish the legislation after the House vote, the AP reported. Reid's move appeared aimed at reassuring House Democrats that if they passed the bill, it would not get bogged down in the Senate. Party leaders confronted a last-minute obstacle in the form of a group of House Democrats who have expressed concern that the legislation's abortion funding restrictions aren't strong enough, the AP noted. Democratic leaders raised the possibility of addressing those concerns with an executive order from the president, the AP added. The legislation would provide health coverage to tens of millions of Americans who are now uninsured, prevent insurance companies from denying coverage to people with serious health conditions and set up marketplaces where small businesses and the self-employed can pool together to get coverage, the AP noted. Critics have said the legislation will add to an already high federal deficit and may not do enough to contain skyrocketing U.S. medical costs.