The Pew Research Firm is helping define the middle class. A battle ground for politics is also so critical for marketers to understand.

Per the Pew summary, here’s a portrait:

12 Percentage of the middle class that say “being wealthy” is very important to them.

14 Percentage of middle class that lost their jobs in the past year — about half the proportion that fear they’ll lose their job in the year ahead.

29 The percentage increase in the inflation-adjusted median net worth of middle-income families from 1983 to 2004. During that same period, the net worth of upper-income families grew by 123%, or four times faster.

33 Percentage of Americans with family incomes of $150,000 or more who say they are middle class.

39 Percentage of the middle class who say they are “living comfortably.” About a quarter — 23% — say they are just able to meet expenses or fall short.

40 Percentage of middle-class homeowners who have paid off less than half of the money they owe on their homes.

41 Percentage of Americans who say they are better off now than they were five years ago, the smallest percentage in more than four decades.

41 Percentage of Americans with family incomes of less than $20,000 who say they are middle class.

53 Percentage of all Americans who identify themselves as middle class.

55 Percentage of Baby Boomers who say their income won’t keep up with the cost of living in the coming year, a view shared by significantly smaller proportions of younger (44%) or older (43%) adults.

67 Percentage of the middle class who say they are doing better than their parents. But only about half (49%) expect their children to do better than they’re doing, down from 61% in 2002.

68 Percentage of middle-class Americans who say “having enough time to do the things you want” is a very important priority in their lives. Other priorities in this survey scored lower: having children (62% rate this very important), having a successful career (59%), being married (55%), doing volunteer or charity work (52%), leading a religious life (53%), and being wealthy (12%)

79 Percentage of adults who say it is harder now than it was five years ago for the middle class to maintain its standard of living, up from 65% in 1986.

89 Percentage of employed middle-class Americans who are satisfied with their job, including 34% who are “completely satisfied.”

$52,285 The median family income of Americans who identify themselves as middle class.

$70,000 The median family income that Americans say is necessary for a family of four to live a middle-class lifestyle in their communities.