The answer depends on what kind of nonprofit we're talking about.
A 501(c)(3) and a 501(c)(4) are very similar but are ruled by different standards when it comes to political activity such as lobbying.
The 501(c)(4), which is typically a civic league or local association of employees that promotes social welfare, may advocate for a political candidate and even a ballot initiative as much as it wants just as long as those activities fall within the organization's primary purpose. However, contributions to a 501(c)(4) are not tax deductible for the donor unless the organization is a government agency or is engaged in public service.
A 501(c)(3), on the other hand is not allowed to engage in political activity unless the money so used is 20% or less of its operating budget, and if the political activity is not for a particular candidate or ballot initiative. The organization can engage in general voter education about issues, even those that could affect its cause, as long as all points of view are represented. A forum with all candidates or both sides of a ballot initiative are examples of acceptable political activity. The 501(c)(3) cannot take political sides.
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