The Senate began a debate Monday over the future of health care in America that's likely to go on for weeks, but behind the scenes, lawmakers are struggling to resolve an even more explosive issue: how to pay for all their ideas.

Federal budget deficits remain at record highs. The national debt is $12.1 trillion and Congress must vote soon to let it go higher or else the Treasury won't be able to issue new debt. President Barack Obama is expected to announce Tuesday a plan to send an additional 30,000 to 35,000 American troops to Afghanistan, which will require more spending.

Despite the Obama administration's promise of a new era of fiscal responsibility, seven of the 12 major appropriations bills that set federal spending — including those that govern the budgets of the Departments of Defense, Health and Human Services and Transportation — still haven't passed Congress.