If it shall appear on the trial of any action brought for the publication of any alleged libel in any newspaper published in this state that the alleged libel was published in good faith, that the publication thereof was due to mistake or misapprehension of the facts, and that a full and fair retraction of any statement therein alleged to be erroneous was published in the same type and in the same position on the same page as was the article complained of as libelous, in the next regular issue of such newspaper, or in case of a daily paper within three days, after service upon the publisher of such newspaper, at the principal office of its publication by the party aggrieved, of a written notice specifying the statement alleged to be erroneous, or, in case such notice is not served in the issue or within the time above specified after the filing of the complaint and service of the summons in said action, then the plaintiff shall recover only actual damages; provided, that if such libel was published in a Sunday edition, the publication of the retraction must have been in a Sunday edition within two weeks after the times above specified; provided further, that this section shall not apply in the case of any libel against any candidate for a public office at any election or primary, or any avowed candidate for nomination to any office before any political convention, unless the retraction of the charge was made editorially in a conspicuous manner at least five days before the holding of such election, primary or political convention in case such libelous article was published in a daily paper, or if published in a weekly paper, at least three days before the holding thereof, which editorial retraction shall be in lieu of any other retraction herein provided for.