NY Times.  It begins:

More than half of the general election advertising aired by outside groups in the battle for control of Congress has come from organizations that disclose little or nothing about their donors, a flood of secret money that is now at the center of a debate over the line between free speech and corruption.

The other day, I mentioned a CCP op-ed stating that over 95% of campaign spending this cycle is funded by groups that publicly disclose (some) donor info to the FEC.

Some of the discrepancy is due to the denominator: the Times piece is counting 55% of broadcast ads by outside groups, and the CCP piece counted candidate and party spending as well as other outside spending.  But on the same denominator, I think that still leaves CCP with “dark money” tallied at $75 million of the $357 million (21%) of spending by those who aren’t parties or candidates.  Has there been that much general election spending by outside groups this cycle beyond broadcast ads?  And if not, any ideas about what accounts for the difference?