Nancy Pelosi pledged Tuesday night that the new Democratic House will deliver campaign-finance reform to “drain the swamp of dark-interest money in our elections.” That’s a little rich. Mrs. Pelosi’s second run at Speaker comes thanks in large part to a green wave of cash that Democrats surfed to political victory.

Democratic House candidates this cycle raised $951 million as of Oct. 17, the most recent reporting cutoff, according to figures from OpenSecrets.org. That’s nearly 50% more than Republicans. Forty-five percent...