RELEVANT EXPERIENCE:  One dwarfs the other, dramatically.

Is it possible to "just add water" and voila! instant management skills - or does it take years to hone this skill to the level where one can be effective.  From my years of experience, and personal frustrations learning management, I absolutely believe that it takes years and years to learn management.  We cannot afford to have a President who needs lots of on the job training. 

If one rates experience and success in managing and actually running businesses, this is how the candidates would stack up.  (This is not from a prejudiced point of view.  It is an assessment, which you, of course, will have to examine for its substance.  It is based on facts and is very, very clear:

                                            Of Experience

Romney                                      10        Brief video clips: 
                                                                                      "Romney is the BEST BUSINESSMAN IN NORTH AMERICA"
                                                                                     Jack Welch:   "In my lifetime, Mitt Romney is THE MOST QUALIFIED
                                                                                         LEADER I'VE EVER SEEN run for the Presidency of the United
Obama                                         2         (He has achieved some experience from being in the White House,
                                                               but as an "amateur" - see Confidence Men, Suskind history
                                                               based on 700 interviews - very revealing of what actually is going
Gingrich                                        1         Also "idea man", but we need a man who gathers more info and
                                                                  reasoned consensus and then implements effectively; not a
                                                                  man who is erratic and at times alienating.
Santorum                                      1         A "social values" strong advocate to the degree it alienates
                                                                  people.  Excessive focus in that area provides a conflict with
                                                                  good, balanced management.

While there may be some disagreement on the rating, I think it would be slight, as facts are facts (and opinions are not facts!).

Harvard Law School

Community Organizer, Professor, Law
  (Taught Alinsky, Rules For Radicals)

State Senator, 1997-2004 (9/99, lost for congressional seat) -                            6 years

US Senator, 2004-2007 (diverted by
   his run for Presidency)                      2 years

Run For President, 2007-2008

President, 2009-2012                            3 years

Time governing, managing -              3 years?
                                               Many mistakes

Harvard Law School, Harvard Business School

Management consultant 

Turnaround and business specialist
(hugely successful) including consulting   25 years

Olympic turnaround,                             2 years

Governor, solved debt crisis and health
care problems (using conservative
principles only)                                        4 years

Run For President

Time governing, managing -                 30 years,