We are roughly 16 hours from the fiscal cliff deadline Washington time and it seems the Obama Administration may have played its final card regarding the Senate negotiations, Vice President Biden:

Senate Minority Leader Mitch McConnell (R-Ky.) and Vice President Joe Biden engaged in furious overnight negotiations to avert the fiscal cliff and made major progress toward a year-end tax deal, giving sudden hope to high-stakes talks that had been on the brink of collapse, according to sources familiar with the discussion.

McConnell and Biden, who served in the Senate together for 23 years, only started talking Sunday, after negotiations between Senate Majority Leader Harry Reid (D-Nev.) and McConnell sputtered.

Meanwhile back in the House, if Speaker Boehner actually wants a deal he is going to have to wrangle the Tea Party faction of his own party, something he has been proven unable to do previously:

The roughly 50 members elected to the House two years ago have been a challenge for the more moderate House Speaker John Boehner since they took office. Perhaps most memorably, many of them refused last year to support a debt-ceiling bill because they said it didn’t reduce federal spending enough.

Just last week they squashed Boehner’s fiscal plan by refusing to compromise and vote on a tax increase for any American, despite the House speaker — in his so-called “Plan B” — having suggested extending tax cuts only for those making more than $1 million annually.

And their most powerful vote might be yet to come, should Tea Party-backed House members reject a possible Senate proposal over the next two days to extend tax cuts and perhaps avert massive federal spending cuts that start January 1.

In the scenario that may – repeat may – play out: Biden and McConnell cut a deal, it passes the Senate and goes to the House but Boehner does not have the backing of the Tea Partiers.

So now does Speaker Boehner get Democratic votes to override opposition from within his own party? Doing so could trigger a leadership challenge. Tick Tock.