Gary Becker writes,

Part of the hostility to campaign contributions reflects a general hostility to advertising found among intellectuals in all spheres, including many economists. This hostility greatly underestimates the importance of advertising in providing information, in helping new products or candidates to compete against the establishment, and in entertaining and providing other satisfactions to those affected, be they consumers or voters.

Of course, my view is that pork-barrel expenditures represent campaign contributions, coerced from the taxpaying public.