According to Obama’s Fox News campaign page, DLA (of dubious journalism awards fame discussed below) has given the president $314,977 (£200,000) – more than Google but less than Microsoft. US outfits Skadden, Sidely Austin, Kirkland & Ellis (also a contributor to Mitt Romney's campaign) and Wilmer Hale are the other law firms in the top 40 Obama donors, coming in at numbers 5, 10, 19 and 20 respectively on Ranker.com's list.
The campaign page also reveals that in total "lawyers & lobbyists" (an odd pair to group together) have contributed a grand total of $14,059,717 (£8,883,940) to the Obama campaign so far.
*OK, so global behemoth DLA Piper is kind of American, too. But it has its roots in Leeds.