Enron gave some money to Dems, as well as to Republicans -- as does pretty much every corporate player. It's called "playing both sides."
Enron gave 73% of its $$$ to Republicans. That's very one-sided, and I doubt that the Dems risk as much in an Enron investigation as the Republicans.
The House side looks pretty ugly for the Rats:
Ken Bentsen (D-Texas) $42,750
Sheila Jackson Lee (D-Texas) $38,000
Martin Frost (D-Texas) $24,250
Charles W. Stenholm (D-Texas) $14,439
Chet Edwards (D-Texas) $10,000
John D. Dingell (D-Mich) $9,000
Edward J. Markey (D-Mass) $8,500