WASHINGTON — Legislation to overhaul the nation's health systems is unlikely to make it through the House and Senate before the August target set by President Obama and other Democratic leaders, lawmakers said yesterday.

Democrats and Republicans alike said the administration's sweeping health care proposals are moving forward on Capitol Hill but cautioned against rushing into a spending plan that could cost trillions of dollars over the next decade. Obama's health and human services secretary said she remains optimistic Congress would send the White House legislation before the year ends.

"I think everything is on the table and discussions are under way," Secretary Kathleen Sebelius said on CNN's "State of the Union."

But the White House's strategy of leaving the legislative back-and-forth to Congress has produced varying and sometimes contradictory versions of health care legislation — along with delays. As the Senate turns its attention to Supreme Court nominee Sonia Sotomayor's confirmation hearings, the focus will turn away from Obama's top domestic priority.

The administration's Democratic partners in Congress hinted they would not deliver legislation before leaving town for an August recess. And while Sen. Chuck Schumer, D-N.Y., insisted on NBC's "Meet the Press" that lawmakers would have the overhaul in place before August, he does not expect Obama to sign it before lawmakers return to their home states.

The House and Senate are working toward legislation that would deliver on Obama's popular goals from his presidential campaign, but they are hardly in unison. Democratic leaders, meanwhile, have tried to calm moderate and conservative lawmakers about a proposal that could make their re-election bids more difficult.

Republicans, seizing on an issue that affects all Americans and has shown a glimmer of hope for an out-of-power political party, have lambasted the proposals as irresponsible. They have tied the plan to out-of-control spending and a bloated federal government.

"I think the bigger issue here is why are we going to increase spending and health care by $1 trillion, $2 trillion, $3 trillion — most of which we can't afford — add that to the debt or add it to the tax burden of the American people?" said Sen. Judd Gregg, R-N.H., on CNN. "Why don't we approach this horse from the other end?"

"There is no chance that it's going to be done by August," said Sen. Jon Kyl, R-Ariz., on ABC's "This Week." "President Obama was right about one thing: He said if it's not done quickly, it won't be done at all. Why did he say that? Because the longer it hangs out there, the more the American people are skeptical, anxious and even in opposition to it."