1. Harold Simmons, Contran Corp. - $20.5 million

T2. Sheldon Adelson, Las Vegas Sands Corp. - $11.5 million

T2. Miriam Adelson, Adelson Drug Clinic - $11.5 million

3. Bob Perry, Perry Homes - $8.5 million

4. Robert Rowling, TRT Holdings, Inc. - $3.5 million

5. Weaver Holdings, Inc. - $3.4 million

*Top donors for 2012 election cycle; numbers through Nov. 26, 2012.

Source: Center for Responsive Politics, Federal Election Commission