The vital provision of the pertinent portions of the statute, Sec. 307, makes its requirements applicable to any person who, by himself or through any agent or employee, or other persons, in any manner whatsoever, directly or indirectly, solicits, collects, or receives money to be used principally to aid, or whose principle purpose is to aid, in the passage or defeat of any legislation by the Congress, or to influence, directly or indirectly, the passage or defeat of any legislation by the Congress of the United States. It is a well established principle that a criminal statute must define the crime with sufficient precision and formulate an ascertainable standard of guilt, in order that any person may be able to determine whether any action, or failure to act, is prohibited. A criminal statute which does not comply with this principle is repugnant to the due process clause and is, therefore, invalid. This is a fundamental principle in our constitutional system, since without it, it would be possible to punish a person for some action or failure to act not defined in the criminal law and which that person had no way of knowing was forbidden.