Washington ? Fearing a backlash, Democrats smoothed the impact of sweeping health care legislation on working-class families Thursday night and steered President Barack Obama’s top domestic priority toward a crucial Senate advance. The most far-reaching overhaul in decades aims to protect millions who have unreliable coverage or none at all.

Republicans on the Senate Finance Committee attacked the bill as riddled with tax increases that violated Obama’s campaign promises, but failed to remove any of them.

After marathon public debate, agreement by the committee is all but certain for the legislation, although no final vote was expected until next week. That formality — Democrats hold a 13-10 majority on the panel — will clear the way for the full Senate to begin work on the measure at mid-month.

The legislation, like a companion bill under construction in the House, would bar insurance companies from denying coverage or charging higher premiums on the basis of pre-existing medical conditions. It also includes federal subsidies to make insurance available to millions who lack it, and it takes steps to slow the skyrocketing growth in health care costs nationwide.