Starting out, the earliest progressives were known as "Georgists" - that is, Henry George and the publication of the book Progress and Poverty. Note the word "progress" in the title. Georgists were not the uniform statist that we would come to know, starting around the beginning of the 20th century. One of George's primary claims to fame was the Single Tax, but more importantly, what impressed young budding would-be-progressives was his agitation for land nationalization. They absolutely loved that one.
Meeting only limited success, they eventually dropped "Georgist" and adopted the name of "Nationalist", following the success of Edward Bellamy's book Looking Backward. Much more statist than a Georgist, the Nationalists were (and still are) deeply fond of the idea of the nationalization of some or all industry in the hands of government. They had increasing nation-wide popularity, much moreso than under the prior banner.
Around the time when Looking Backward's popularity was waning, there was a lack of unity of what to call themselves. Some progressives decided to be called Populists, and had their own Populist party that again, still, sought greater government intervention. Others simply decided to call themselves "reformer". The populists again were even more popular than their prior iteration, even running their own presidential candidate. The Nationalists never got that far and neither did the Georgists.
Finally, right around the turn of the 1900s the word 'progressive' became vogue in all corners of modern statist academia and among pro-big-government activists on the street. The movement that would inevitably become the "progressive movement" again split, this time succeeding in gaining the presidency in Theodore Roosevelt. Another half of progressives coalesced behind Bryan and then later Wilson, the second big-government progressive to become president.
It wouldn't be until the 1930's and Franklin Roosevelt that the progressives had to again take a new title. But this time, they took a new title for a different reason: They had thoroughly scared the crap out of the American people. Americans for the first time saw progressivism in action for what it actually is and not just nebulous propaganda dressed up in cute words. Every prior re-branding of progressivism was simply due to a failure to reach critical mass. But now, they were in active camouflage. They were hiding, they were wearing masks, masquerading in disguise, something they had never really had to do before.
Under the banner of "liberalism", progressives have had nearly a century to hide their true means and ends. With every prior name change, progressives could pretty much make something up and chart their course forward. But their movement was almost completely destroyed in the 1910's-20's, and this time they took over an already existing label: "liberalism". This label wasn't being used much and it was not the clean slate that they were used to. However, by taking over a previously known moniker, "liberalism", they found themselves gaining a much thicker layer of camouflage than they had expected to receive. It didn't require the kind of marketing that would've been necessary for a wholly new word.
But eventually, that camouflage began to see its disintegration in the mid-late 2000s, leading some prominent progressives to take off their masks and admit that they never were liberals at all - they were progressives all along and had been for decades. One even did so in a presidential debate.
Tody, there is not a unity among progressives as to whether or not they should reclaim the name of 'progressive', or continue to try to stay incognito under the banner of liberalism, or should they follow Bernie's lead?
As I said in the opening, I think progressives might jump ship altogether and go with what is largely a clean slate. That is their history, it's what they've always done. They've never gone back to a name that they had already used in some prior time. Even when they took over the word "liberalism", it was largely a clean slate.
The word "Technocrat" invokes the "good name" of science, and the media has over the years seeded the ground with plenty of good will toward this moniker.
Could lucky number seven - "Technocrat"; Technocracy - could this moniker lead progressives once and for all toward the salvation they've always sought? Only time will tell. The name of liberalism is fading fast, and a widespread return to "progressive" may not provide the relief they are seeking.