What's next in the Senate health care debate

— -- Despite all the activity on the Senate floor Tuesday -- including a standing ovation for the recently cancer-diagnosed Sen. John McCain, R-Ariz., who flew back at the last minute to cast the decisive vote -- the chamber only passed a procedural measure to move forward and kick off debate on the repeal-and replace legislation that the House passed back in May.

Now the work begins. Over the next few days, senators will introduce amendments changing the House version and decide the final text of a bill they will vote on and try to pass.

After the vote Tuesday to move ahead to debate, Senate Majority Leader Mitch McConnell, R-Ky., introduced two possible amendments that would swap out the House text entirely and replace it with new language.

The first, a package that included the repeal-and-replace draft Senate leadership wrote up this summer but never made it to a floor vote, failed on a series of procedural votes Tuesday night.

But the Senate has yet to consider the second possibility that McConnell introduced, which would swap out the House version with the text of bill lawmakers voted on back in 2015 that repeals the Affordable Care Act but with a two-year delay to leave allow time to pass a replacement.

This language passed both chambers of Congress back then, but even Senate Republicans acknowledge that was a vote to send a message to President Barack Obama and to their voters back home because they knew it was going to get vetoed. Recently, several Republicans have said they won’t back a straight repeal option like this and, as of now, it will likely fail.

Once those two options are voted on, the Senate will have more debate time (18 hours divided evenly between Democrats and Republicans) and then a so-called vote-o-rama begins, opening the floodgates for all senators to introduce as many amendments as they want. The vote-o-rama can last until senators reach literal physical exhaustion.

Democrats have said they have "hundreds" of amendments to offer and are preparing for a marathon.

Sen. Rand Paul, R-Ky., and other Republicans have said leadership will likely continue to offer more limited repeal options that narrow the scope of repeal, until they hopefully get something to pass.