npr.org

Every presidential nominee going back to 2000 has revealed the names of influential supporters known as “bundlers” because of the way they persuade others to give money to a candidate. Every nominee, that is, until Mitt Romney.

The most anyone can give directly to any presidential campaign is $5,000, and everyone who gives that much is listed in the Romney campaign’s monthly disclosures.

When it comes to the bundlers, though, the campaign chooses to keep those names secret.