The most likely way I see this going is with many left-moderates saying to themselves "we stuck by Teddy through the war, we stood with him against the strikers, and he just spat in all our faces," especially when his administration uses their new freedom to crack down indiscriminately on instruments of organized labor across the board - with AFL affiliates being pulled into wildcat strikes, I doubt the USIC will treat reformist unions with kid gloves. Some left moderates will just wring their hands or try and rein his administration in, but others will jump over to supporting the strikers, even if it's only out of seeing the way the political winds are blowing. If there's a crackdown that spills over into hurting members of respectable society, we could see the protest movement snowball out from just organized labor, into more and more groups that politicians can't just demonize and minimize. If pastors across the nation are sending around collection plates for strikers, if small business owners are calling on their representatives to say that America must surely be able to do something for its hardworking men so the country can return to peace and prosperity, then the administration would need to eventually cave.
But hey, maybe the administration is spoiling for a fight, and it's time for accelerationism! If the turn in public sympathy, against the government and towards the strikers, is matched with a growth of strike management organizations, various self-directed citizens bodies for providing parallel government instead of respecting the corrupt system, then maybe the feds will see it as a fundamental threat to the state - since it's a direct threat to the power of the existing federal institutions. Federal law enforcement won't be able to operate easily where it doesn't have the consent of local law enforcement, and if their authority is eroded enough, they might resort to measures that instigate a constitutional scrap with recalcitrant states. Not to mention, of course, that all these escalating measures would only erode sympathy and trust, and if strike organizations manage to keep the peace, maintain essential services, keep people fed (or even keep local small shops open, depending), and in general keep the middle classes from clamoring too hard for escalating intervention, then they might come out of it with lasting control of local governance in various places, and probably be very well placed for the upcoming elections. And yeah, I don't really see the case yet for a successful revolution - it could be a partial one, with success cases that can demonstrate an effective governmental model for America, such that when the next crisis hits, more and more people can turn to it and make it work, enough that when institutional resistance takes the inevitable military form, the socialist coalition will be strong enough to win without a widespread, years-long bloodletting, I would hope.