The picture below shows a larger view of this Old Howdy Doody For President Advertising Political Tin Tab Button. The button is not dated but is believed to be from the 1970s. It may have been from a Howdy Beef n' Burger Restaurant. It has a nice image of Howdy Doody and it is marked as follows:
HOWDY DOODY FOR PRESIDENT HOWDY! COPYRIGHT NBC
The button measures 1-1/2'' wide. The tab was bent and straightened but it appears to be in good condition with some light wear as pictured.