WASHINGTON (AP) — House Republicans vowed Wednesday to pass legislation that would prevent a partial government shutdown and avoid a historic national default while simultaneously canceling out President Barack Obama's health care overhaul, inaugurating a new round of political brinkmanship as critical deadlines approach.

Obama swiftly condemned the effort as attempted political extortion, and the Republican-friendly Chamber of Commerce pointedly called on lawmakers to pass urgent spending and borrowing legislation — unencumbered by debate over "Obamacare."

The two-step strategy announced by House Speaker John Boehner marked a concession to his confrontational rank and file. At the same time, it represented a challenge to conservatives inside the Senate and out who have spent the summer seeking the votes needed to pull the president's cherished health care law out by its roots. They now will be called on to deliver.