The Convention "floor fight" is a mythological sort of deal for Democrats. There have been some special Conventions, where no candidate arrives with any sort of even a close majority and it takes several votes to figure out who it will be.

1968 was the anti-Vietnam War protest elevated to an art form and McCarthy first getting 42% to Johnsons' 49% in New Hampshire primary. Johnson announced he was going to not run for a second term.  Robert Kennedy got into the race, Hubert Humphrey the VP got into the race, and when RFK got shot the night of the California primary (winning it), it threw the Convention into turmoil. MLK had been shot on April 4th. One hundred cities rioted and looted.  Another war supporter, Humphrey managed to get the insiders to pass by a discouraged RFK contingent and a Eugene McCarthy in Chicago to get the nomination.

 The police were sent around the delegates hotels to keep order.  Senator Abraham Ribicoff in giving a speech placing McCarthy's name in nomination scolded and told of Daley for his tactics. The NY and California delegations, after Humphrey succeeded in getting the nomination,
lit candles and swayed singing protest songs right on the floor of the Convention. Dump the Hump!  

It was a unpopular choice.  Nixon won by a small margin.  HHH was linked too closely to Johnson , and no enthusiasm for him was seen in most areas.  TV coverage of the controversies to people who didn't get what was going on proved a bigger help to the Republicans.  Their convention was very orderly.

Convention excitement is overrated. Unfortunately a troubling picture will create negatives among low-info voters.