Except as otherwise authorized in this act, no person holding office or employed under the provisions of this act shall be an officer or employee of any political party or organization, actively engaged in the work or campaigns of any political party or any candidate for public office or contribute work, money or property of value to any political party or organization or to any candidate for public office: Provided, That this prohibition shall not deny the right of such officer or employee to vote in any election. Violation of any of the provisions of this section shall be grounds for discharge from employment.