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The 2020 Democrats have lurched so far left that even some of their own party leaders are starting to cringe. Former Obama administration officials, for instance, are now desperately urging their Party's presidential candidates to stop advocating for controversial open-borders immigration policies.

During a recent interview with CNN’s David Axelrod — who himself served as a senior advisor to Obama — former Attorney General Eric Holder emphasized the importance of enforcing America’s immigration laws, arguing that the Democrats “have to understand that we do have to have borders,” because “borders mean something.”

But Holder wasn’t finished. When asked if he supports “decriminalizing” unlawful border crossings — an outrageous proposal that is rapidly gaining traction on the left — Obama’s former attorney general promptly replied, “no.”

“I mean, the law that is on the books has been there for about 100 years now or so,” he explained. “It might send the wrong signal, but it would certainly take a tool away from the Justice Department that it might want to use for an individual case and for some reason.”

Holder isn’t the only seasoned Democrat to criticize the progressive stance on immigration in recent weeks. John Sandweg, a former acting director of Immigration and Customs Enforcement (ICE) in the Obama administration, told BuzzFeed News last month that he objected to the liberal attacks on President Obama’s deportation practices, pointing out that Obama tried only to deport convicted criminals and people apprehended in the act of crossing the border illegally. Sound familiar? It’s just that when President Trump enforces existing laws, it represents an opportunity for the 2020 Democrats to score political points.

Former Democratic Senate Majority Leader Harry Reid also recently admitted that decriminalizing border crossings is a horrible idea — especially when it comes to the Democrats’ electoral prospects.

“There are so many more important things to do,” Reid told VICE News. “Decriminalizing border crossings is not something that should be at the top of the list. It should be way, way down at the bottom of the list. People want a fair immigration system. They don’t want an open-door invitation for everybody to come at once.”

Old-school Democrats such as Holder, Sandweg, and Reid — as well as former Obama DHS Secretary Jeh Johnson, who was among the first to challenge his Party’s increasingly radical stance on immigration — are now distinctly in the minority within the contemporary left, though. Radical progressives and so-called “democratic-socialists” have taken control of the Democratic Party, and they’re steering it away from the political center and straight towards the rocky shoals of political extremism. Former Vice President Joe Biden was even forced to defend Obama’s immigration agenda from a relentless blitzkrieg of liberal outrage, despite the fact that Obama was further to the left on immigration than any president in American history.

The full-throated embrace of open borders by Democrat presidential candidates will prove to be its downfall in the 2020 presidential election — and long-time Obama allies know it.

Polling has consistently shown that open-borders policies, such as decriminalizing illegal border crossings and granting amnesty to illegal immigrants, are deeply unpopular — even among Democratic voters. Republicans, of course, are almost unanimously in favor of securing America’s borders, but perhaps the most worrying revelation of all for the Democrats is that independent voters tend to agree with the GOP on this issue.

The Democrat candidates are staking the outcome of the 2020 election on their radical open-borders immigration policies. That approach might be popular on the far-left fringe of the electorate that dominates the primary contests, but the only Democrats with any experience winning national elections — and with managing a border crisis — know that it will be political suicide for their nominee to defend such a deeply-reviled proposal during the general election.

Art Del Cueto is Vice President of the National Border Patrol Council.