Oil giant Exxon Mobil — the largest corporation in America — spent $9.32 million on lobbying in the first three months of 2009, more than any other company in the nation, according to recently released lobbying filings. Joining Exxon in the top four were competitor Chevron ($6.8 million), defense contractor Lockheed Martin ($6.35 million) and drug maker Pfizer ($6.14 million).

About 100 companies and about 20 trade groups spent more than $1 million on lobbying in the first quarter, about the same as last year, according to lobbying reports filed Monday. Most of these companies are in the energy, pharmaceutical, insurance and telecommunications industries.