United States President Barack Obama has promised to push a reform package through Congress this year despite growing doubts about the plan, even among fellow Democrats.
Mr Obama said on Wednesday a broad healthcare overhaul was critical to an economic recovery as the biggest driving force behind the federal deficit was skyrocketing healthcare costs.
Leaders in Congress have struggled to find common ground on the cost and scope of a healthcare plan, Mr Obama's top legislative priority.
Hopes dimmed in Congress that lawmakers could meet the president's goal of passing early versions by the August summer recess, but Mr Obama appealed to congressional leaders to help Americans facing higher insurance premiums or lacking insurance.
"They are looking to us for leadership, and we must not let them down," he said.
The measure faces opposition from all sides, with a group of conservative Democrats questioning the cost and funding, liberal Democrats concerned it would not do enough and Republicans blasting the $US1 trillion-plus price tag.
Mr Obama had stepped up his involvement, meeting with rebellious House of Representatives Democrats at the White House on Tuesday and scheduling healthcare events throughout the week, topped by the nationally televised news conference on Wednesday.
The overhaul is designed to create a government-run insurance program to compete with private insurers, expand coverage to most of the 46 million uninsured Americans and hold down soaring healthcare costs that are rising faster than inflation.