If Romney loses in 2012, there is no way he runs in 2016. His time to run will have passed.
2012 is do or die politically for Romney.
This election is winnable for Romney. I say winnable, not a certainty. It is far from a certainty, for either candidate I might add.
Romney is running against a candidate who has turned in a less than sterling performance during his term. 12.7 million unemployed, 5 million of them for more than six months. (CNN)
According to this forecast, unemployment is expected to be 8.4% in October, not a good unemployment number just before the election for a President running for re-election.
http://www.forecasts.org/unemploy.htmU.S. Civilian Unemployment Rate Forecast
Percent Unemployed, Seasonally Adjusted
1 May 2012 8.2
2 Jun 2012 8.1
3 Jul 2012 8.1
4 Aug 2012 8.2
5 Sep 2012 8.3
6 Oct 2012 8.4
Updated Friday, May 18, 2012
So yes, this election is winnable for Romney.
But Romney has to quit shooting from the lip and stay on message. He has to avoid making gaffes, and he has made plenty of them during this campaign.