With voters headed to the polls on Saturday in South Carolina's "open" Democratic primary, critics are warning President Donald Trump to be careful about what he publicly wishes for after he encouraged Republicans supporters at a rally in the state Friday night to back Sen. Bernie Sanders—declaring him the easiest candidate in the 2020 field to beat in this year's general election.

"Who would be the best candidate for us—not for them?" Trump asked the crowd inside a packed arena in North Charleston.

Trump proceeded to ask the audience who should be included in the makeshift-realtime poll—deciding that Amy Klobuchar, Tom Steyer, Pete Buttigieg, Elizabeth Warren (who he again racistly referred to a "Pocahontas"), and Michael Bloomberg (who he called "Mini-Mike") should be left out—and ended up with just Joe Biden ("Sleepy Joe") and Sanders (who he refers to as "Crazy Bernie").

"In other words, who is the weaker of the two?" Trump continued, asking his followers to indicate their preference by cheering. "Meaning, we put it into very simple language: Who the hell is easier to beat?"

Though it was very difficult to judge the difference, based on the video of the rally, Trump concluded: "I think maybe Crazy Bernie has it by a little bit."

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Denounced by some Trump critics as a clear case of "ratfucking"—a term used to describe political sabotage and dirty tricks—others warned that the president's effort to interfere in the Democratic primary may not be what it seems and could very easily backfire on him.

Both national and battle-ground state polls consistently show ("here's the math") that Sanders beats Trump in head-to-head matchups—something the Trump campaign is very aware of. As Common Dreams reported last month, a leaked 2018 recording revealed Trump admitting in private that, during the 2016 presidential race, Sanders was the "only one I didn't want [Hillary Clinton] to pick" for vice president following the Democratic convention.

Like the blowback Clinton faced in 2016, when many in her campaign believed that Trump would be a more vulnerable rival in the general election, Sanders supporters responded with notes of caution about the president's remarks:

Careful what you wish for! https://t.co/aosVVsuU1T — brandon (@OctaviusCramer) February 29, 2020

Is it that Trump thinks Bernie is the weakest candidate, or that the president is trying to weaken the Democrat who he knows poses the greatest threat?

Earlier this week, Sen. Tim Scott, one of South Carolina's two Republic senators, said plainly his belief that Sanders has the best chance of defeating Trump in a general election. "Bernie Sanders brings that outside game in a similar fashion that President Trump did in 2016," Scott said in a CBS interview.

While it's obvious that Trump calling Sanders the "weakest candidate" or the "easiest to beat" is the same argument made by Bernie's Democratic rivals who say the Republican attack machine will have a field day in a general election, it might also be true that Trump's latest antics actually have the same intent as Biden and Bloomberg's: keeping the nomination away from Sanders.

As Kaushik Basu, former chief economist of the World Bank, wrote in a Project Syndicate column this week, it doesn't take "but a little game theory" to realize that those most invested in the president's reelection recognize that Sanders is "the only candidate who can defeat Trump."

Ahead of Trump's rally, Sanders condemned the president's decision to travel to South Carolina on the eve of the primary to "disrupt" the Democratic primary, especially as the country faces the spreading threat from coronavirus.

"It's pathetic and unacceptable that, while reports of coronavirus infection continue to grow and economic concerns rise," Sanders tweeted, "Donald Trump is flying around playing his own political game, traveling to South Carolina in an attempt to disrupt the Democratic primary."

Meanwhile, at a rally of his own in the Super Tuesday state of Massachusetts, Sanders told a crowd of thousands in Springfield that it would be his campaign's "movement of love and justice" that "will defeat Trump's hate and greed."

"When we care about each other, when we create what Dr. [Martin Luther] King called a community of love, we become better human beings," Sanders said.