WASHINGTON -- Senate Republicans and Democrats gridlocked Tuesday over competing proposals to ease the impact of across-the-board spending cuts blamed for furloughs of air traffic controllers and flight delays for millions of travelers.

With Republicans blaming the administration for the inconvenience, Senate Majority Leader Harry Reid proposed immediate passage of legislation to scrap the spending cuts and make up the money by canceling funds ticketed for the wars in Iraq and Afghanistan.

Sen. Tom Coburn, R-Okla., swiftly blocked the move, reflecting the view that those funds will never be spent and shouldn't be used to offset cuts. He countered by proposing President Barack Obama submit a replacement plan for the across-the-board cuts, but Democrats swiftly rejected his alternative.

At issue are the cuts of $85 billion that began in March, a reduction of 5 percent from domestic agencies like the Federal Aviation Administration and 8 percent from the Pentagon. They are required because of the failure of Washington to follow up a 2011 budget pact with additional spending cuts.

The cuts would require many federal workers to absorb pay cuts with forced furlough days. Lawmakers have been particularly upset with the air traffic delays and announced closures of control towers at rural airports. Economists warn that the cuts will slow the recovery of the economy but Republicans and President Barack Obama have been unable to agree on a way to repeal them and replace them with other cuts or tax increases.

The Senate is debating legislation that would empower states to require online retailers to collect state and local sales taxes for purchases made over the Internet. That legislation is expected to occupy the chamber through the end of the workweek; senators are expected to then break for a one-week vacation.