The Republican are on the payrolls of all of the rich Republican campaign contributors.

The Democrats are on the payrolls of all of the rich Democratic campaign contributors.

Both are on the payrolls of the corporations that make massive campaign contributions, usually to both sides.

Another difference:

The Republicans love to give away huge quantities of money to rich Republicans.

The Democrats love to give away huge quantities of money to rich Democrats.

Both love to give away huge quantities of money to corporate campaign contributors.

Finally:

The Republicans try to solve problems with expensive and wasteful programs that do not work.

The Democrats want solve these problems with other programs that are even more expensive and more wasteful and also do not work.

The differences are great, as are the differences between Tweedledee and Tweedledum.