Republi-cons also hurt the bottom line, profit. See New York Times, Bulls, Bears, Donkeys and Elephants, which states:
"Since 1929, Republicans and Democrats have each controlled the presidency for nearly 40 years. So which party has been better for American pocketbooks and capitalism as a whole? Well, here’s an experiment: imagine that during these years you had to invest exclusively under either Democratic or Republican administrations. How would you have fared?
As of Friday, a $10,000 investment in the S.& P. stock market index* would have grown to $11,733 if invested under Republican presidents only, although that would be $51,211 if we exclude Herbert Hoover’s presidency during the Great Depression. Invested under Democratic presidents only, $10,000 would have grown to $300,671 at a compound rate of 8.9 percent over nearly 40 years."
The article includes a nice graph the Obama campaign should run in an ad.