Washington (CNN) - Congress is demanding answers in its investigation of the Gulf of Mexico oil spill - and the BP executives likely to be grilled in the weeks ahead are no strangers to the ways of Washington.
The company spent almost $16 million lobbying Congress in 2009 and over $3.5 million so far this year, according to the non-partisan Center for Responsive Politics (CRP).
BP employees also gave over $3 million in campaign contributions during the last decade, and almost $110,000 in 2010.
Fifty-seven percent of BP's contributions went to Republicans, while 43 percent went to Democrats.
BP America President Lamar McKay has been asked to appear next week before the House Energy and Commerce Committee - whose members received the largest share of BP's campaign contributions over the last two election cycles, CRP notes.
The congressional investigation comes as BP's ruptured undersea well off Louisiana continues to spew about 210,000 gallons - or 5,000 barrels - of crude a day into the Gulf of Mexico. Efforts to corral the rapidly growing oil spill have so far been unsuccessful.
There is currently a sheen of oil ranging up to 60 miles across and threatening the coasts of Louisiana, Mississippi and Alabama, as well as the Florida Panhandle, according to the National Oceanic and Atmospheric Administration. The overall area impacted by the spill, CNN estimates, is almost as large as the state of Delaware.
An April 20 explosion on BP contractor Transocean Ltd.'s Deepwater Horizon drilling platform left 11 men presumed dead.
- CNN's Dana Bash and Alan Silverleib contributed to this report