Their finances are pretty much constructed in the same fashion: Ponzi.
The criminal "investment advisor" gave hundreds of thousands of campaign contributions to Democratic causes. As Chairman of the Democratic Senatorial Campaign Committee, Chuck Schumer (D.-N.Y.) finagled most of the donations. Madoff even handled Democratic Sen. Frank Lautenberg (N.J) family's charitable foundation. (Which is, regrettably, probably gone now.)
There doesn't appear any quid-pro-quo between the Democrats and Madoff, but there's no doubt Madoff was financially connected to the party and in a much bigger way than Jack Abramoff was connected to the GOP.
Madoff's books looked a lot like our federal government's, too. The only difference is that senators don't go to jail when they lose our money.