I've posted before about the attempts in Congress to legislate/regulate the issue of United States ("US") commemorative coins (See:
Regulating US Commemorative Coins and
Regulating US Commemorative Coins - Redux / Part I to review.). The discussion of this in Congress appears to have had a positive impact on sales of the 1936 Norfolk Bicentennial/Tricentennial Half Dollar.
In summary, in 1939, multiple bills were introduced with the objective of creating a Commemorative Coin Commission that would review all commemorative coin bills introduced in Congress (and referred to the appropriate committee in either the Senate or House of Representatives ("House")). If the Commission deemed the proposal of "sufficient national importance", the bill would be OK'ed to proceed with further consideration. If the Commission did not approve of the bill's theme/objective, no further action on it was to be allowed.
For the optimistic US commemorative coin collector, such bills would have opened the door on possible new commemorative coins.
Major Francis E. Turin, Manager of the Norfolk Advertising Board ("Board"), the sponsor/distributor of the 1936 Norfolk half dollar, reported in January 1940 that "a larger number of coins had been disposed of during January [1940] than in any month of 1939." He suggested that the sales bump was likely tied to the actions in Congress.
At the time, the Board reported that it had approximately 4,000 Norfolk half dollars in inventory (i.e., unsold coins) and was considering returning them to the US Mint to be melted. The potential renewal of issues in the US commemorative coin series appears to have triggered the sale of 100+ Norfolk coins - several years after the coin's release. Turin also noted that he had received multiple requests for pricing for bulk orders of the coin (from collector/speculators and coins dealers).
Turin expected the renewed interest to be sufficient to clear out the Board's remaining inventory - it was not. Thousands of the coin were eventually returned to the Mint.
The fickle collector - you never know exactly what will trigger his/her "I need one!" impulse, but few want to miss out on an opportunity!
1936 Norfolk, VA Bicentennial/Tricentennial Half Dollar

For other of my posts about commemorative coins and medals, including other stories of the Norfolk half dollars, see:
Commems Collection.