Thousands of federal workers are being furloughed Tuesday because the government has shut down for the first time since 1996. Republicans and Democrats in Congress are in a stalemate over a stopgap spending bill and the insistence of House conservatives to strike a blow to President Obama's health care law.

A quick look at what you need to know for Tuesday, Oct. 1, which also marks the beginning of open enrollment for the law known as "Obamacare":

FIRST TAKE: Nobody blinked

STORY: Government shutdown begins

MORE: 66 questions and answers about the shutdown

Where the legislation stands: The House voted 228-199 early Tuesday to start formal negotiations with the Senate on a bill to fund the government for six weeks. House Majority Leader Eric Cantor, R-Va., was appointed to lead the talks for the House — if they ever happen. Senate Majority Leader Harry Reid, D-Nev., is insisting that there will be no negotiations under the present circumstances. The Senate will convene at 9:30 a.m. ET. The House's workday begins at 10 a.m. ET.

What Obama is doing: He's meeting at noon at the White House with beneficiaries of the Affordable Care Act. Obama has told Republicans repeatedly he will not give in to anything that undermines the health care law, and chided them for trying to "refight the results of an election." He telephoned congressional leaders on Monday to say it's up to them to pass a budget on time.

Which federal employees are staying home: Anyone deemed not essential by their agency or department, or more than 40% of the federal workforce. That includes about half of civilian defense workers. All active-duty military personnel are expected at work Tuesday. Still on the job are federal workers whose duties include protecting public health, safety or property. Also, federal employees whose jobs are funded by user fees or permanent spending laws will be working, as will political appointees.

How the parties are voting: The votes on stopgap spending bills have been mostly along party lines in both chambers of Congress. Republicans support attaching restrictions to affect the health care law, Democrats (and the two Senate independents who vote with them) do not. On the House vote to begin formal budget talks with the Senate, there were nine Republicans who bucked their party and voted "no" and seven Democrats who sided with the GOP and voted "yes."

Another fiscal fight looms: While the shutdown has begun, another clock is ticking. The federal government will run out of money to pay its bills by Oct. 17 if Congress doesn't approve an increase to the nation's $16.7 billion debt ceiling. Obama has said he won't negotiate on this point, either.