This competition, geared toward fundraising for MODA at the end of the year, holds the same square shape that they use in all of their icons.
The concept here is that the recipients of the MODA email have probably supported MODA in some way throughout the year to be on their mailing list (whether that is monetarily, becoming a member, or just visiting the museum and showing support by appearance). MODA is saying that without all of this support, they wouldn't exist. This is highlighted by the knockout MODA logo from the red, almost giving the logo a negative space. The only thing that brings the logo back to red is the ribbon on the third box, showing that the gift of support is what keeps MODA alive.
In the copy, MODA thanks everyone for the general support (whatever form that may take) and asks for a donation to keep the support going. By thanking individuals beforehand and acknowledging that patrons of the museum is what makes a museum, I think more people would be willing to donate and would actually be happy to.