How do You Convert Your Direct Mail Recipients to

[slice2020]

I run a nonprofit and our main marketing asset is a direct mail list of 50,000 names - but all physical addresses. Our email list pales by comparison - and in fact pales in comparison to most of our competitors. We would LOVE to convert our snailmail list to email, but it's a challenge. Are there best practices for getting your list off of the very expensive and time consuming direct mailings and onto email? Thanks for any suggestions.
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