19 October 2012 Last updated at 14:04 ET

Top 10 US political donors

Here's a guide to the biggest political donors in the 2012 US election, which is on track to the most expensive ever.

Republican		Democrat
	Sheldon Adelson, 79, donated$34.2m. Owner, Las Vegas Sands casino empire. Based in Las Vegas, Nevada. Worth an estimated $25bn, Mr Adelson also owns resorts in Singapore, Macau, and Bethlehem, Pennsylvania. He gave $10m to Restore Our Future, an independent group that backs Mitt Romney. He also donated $24m, along with family members, to committees backing former presidential candidate Newt Gingrich.		Jeffrey Katzenberg, 61, donated$2.5m. Chief executive, DreamWorks Animation, a film production company. Based in Los Angeles, California. Mr Katzenberg gave $2m to the fundraising group Priorities USA, which supports Barack Obama. The film-maker has also raised over $500,000 by "bundling" or independently fundraising for the president. And he contributed $66,000 directly to the Obama campaign and Democratic party.
	Harold Simmons, 81, donated $16m. Owner, Contran Corp, a metals, chemical production and waste management conglomerate. Based in Dallas, Texas. The fundraising committee American Crossroads received $11m from Mr Simmons, and he gave $800,000 to Restore Our Future. With his wife, Annette, Mr Simmons gave $2.2m to former presidential candidates Newt Gingrich, Rick Santorum and Rick Perry.		Irwin Jacobs, 78, donated $2.1m. Founder and former chairman, Qualcomm, a mobile phone manufacturer. Based in La Jolla, California. Groups that support the Obama campaign received $2m from Mr Jacobs, who also gave $23,000 to Mr Obama and the Democrats directly.
	Bob Perry, 80, donated $15.3m. Founder, Perry Homes, a property firm. Based in Houston, Texas. With a fortune of about $650m, he gave $9m to Restore Our Future and $6.5m to American Crossroads. Earlier this year, he donated $100,000 to a group backing ex-Republican presidential candidate Rick Perry (no relation).		Fred Eychaner, 67, donated $2m. Founder Newsweb Corp, an alternative-newspaper publisher. Based in Chicago, Illinois. Priorities USA got $1.5m from the Midwestern publisher, which is also a "bundler" for the president, bringing in more than $500,000 that way.
	Robert Rowling, 58, donated $4.1m.Chief executive, TRT Holdings. Based in Dallas, Texas. Mr Rowling's companies include Gold's Gym, Omni Hotels, Tana Exploration and an oil company. He gave $4m to American Crossroads in personal and corporate donations, and contributed $100,000 to Restore Our Future.		Jon Stryker, 54, donated $2m. Philanthropist. Based in the state of Michigan. Mr Stryker, who is heir to Stryker Corporation, a medical supply company started by his grandfather, has given $2m to Priorities USA and $66,000 to the Obama campaign and Democratic party.
	William Koch, 72, donated $3m. Owner, Oxbow Corp, energy and mining consortium. Based in southern Florida. Mr Koch, who is thought to be worth about $4bn, has given money to both Republican and Democratic candidates in the past. In 2012, he gave $3m to Restore Our Future in a personal capacity and through his companies.		Steve Mostyn, 41, donated $2m. Personal injury lawyer. Based in Houston, Texas. Mr Mostyn donated $2m to Priorities USA and has also funded Democratic races within Texas.