WHY DO THE GREATEST NUMBER OF INTEREST GROUP CONTRIBUTIONS GO TO
INCUMBENTS REGARDLESS OF THEIR PARTY OR POLITICS?

Hello,

Donors' thinking is as follows: Incumbents almost always win. We want
to be on good terms with the people who will win. Therefore, we will
back incumbents. The National Legal Center for the Public Interest
calls this "buying insurance against ill-treatment." (1)

The point of these contributions is to buy access to policy-makers,
not necessarily to determine who those policy-makers will be. That's
why most corporate donors will contribute to members of both major
parties. As Prof. Paul S. Herrnson of the University of Maryland says:
"These business contributions that go overwhelmingly to incumbents are
first and foremost designed to influence legislation, not election
outcomes." (2)

Note that this is not the case with all donors. "Idealogical" PACs
especially will contribute only to candidates who already back their
stand (and who have a chance of winning).

I hope this answer meets your needs. If not, please request
clarification.

References

(1) National Legal Center for the Public Interest, "Campaign Finance:
Be Careful What You Pray For"
http://www.nlcpi.org/books/watch51/jlwrxxi_May00.htm

(2) David Nitkin, "Corporate Gifts Flow Mostly to Incumbents."
http://216.239.39.100/search?q=cache:HKrvNfcApOIC:www.progressivemaryland.org/news/archive/Corporate%2520gifts%2520flow%2520to%2520incumbents.pdf+contributions+incumbents&hl=en&ie=UTF-8

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