(CNN) Cast into the political wilderness by Donald Trump's election and a run of of congressional cycles dominated by Republicans, US Democrats are locked in a contentious search for a defining message -- and revamped slate of policies -- to lead them back to power.

The UK's Labour Party, in a similar pinch but with a general election less than a week away, has taken the progressive populist route. Jeremy Corbyn's unexpected rise to leadership in the fall of 2015, months after another romp by former Prime Minister David Cameron's Conservatives, represented a sharp left turn for the party, which under Tony Blair and his successors had mostly run parallel with the (Bill) Clinton-era Democrats.

Now, with another UK vote nearing (it's on June 8), Labour ally Ken Loach, the British director, has produced a film/ad -- shared online by Corbyn -- that could offer some insight into what the Democratic party might look and sound like in the coming years, should it choose a similar path to Labour.

We have had enough. We demand a fairer society, #ForTheMany, not the few. Please watch and RT this powerful film by Ken Loach. #WeDemand pic.twitter.com/QpzfUK2HNB — Jeremy Corbyn (@jeremycorbyn) June 2, 2017

You'll be unsurprised that Corbyn has a fan in Sen. Bernie Sanders, who in the UK this week suggested "there is a real similarity" between the ongoing campaign and his own efforts in the US.

"(Corbyn) has tried to transform that party and take on a lot of establishment opposition," Sanders said. "That is exactly what's taking place in the United States and what I'm trying to do with the Democratic Party."

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