For many political conventions there are "hot button issues" and then there are just "hot buttons."
The use of campaign buttons for candidates and slogans dates all the way back to our first President, George Washington. Washington's supporters wore a brass clothing button. The next evolution in the button came with ferrotype and tintype images.
The election that is said to have propelled the use of the campaign button onto the political landscape was the 1896 race between William McKinley and William Jennings Bryan. "As if there were anything in the law or the constitution that made the distribution of a campaign button one of the prerequisite qualifications to the presidency," wrote the Omaha Daily Bee in 1896.
The 1896 button campaign designs were created by placing a thin layer of celluloid over a paper image.
Here's what's on tap so far for the GOP and Democratic Party conventions.