Dean Obeidallah, a former attorney, is the host of SiriusXM radio's daily program "The Dean Obeidallah Show" and a columnist for The Daily Beast. Follow him @DeanObeidallah . The opinions expressed in this commentary are his.

(CNN) Hours before "Saturday Night Live" aired, Donald Trump was serving up some of his own comedy. This time it was in Pennsylvania at a rally in support of Republican Rick Saccone, who is facing Democrat Conor Lamb in a special congressional election slated for Tuesday. And, once again, Trump gave us another example of why Trump is his own -- and potentially the GOP's -- worst enemy.

Holding court in front of an adoring and energized crowd, Trump went off script. In fact, according to CNN, Trump delivered only " about five minutes " of what had been scripted.

The rest was pure, unadulterated and unfiltered Trump.

The rally's highlights therefore had little to do with the GOP candidate who Trump was there to endorse, or even much to do with Trump's political agenda. Instead, one of the top headlines was "Trump Slams NBC's Chuck Todd at Rally: 'Sleepy-Eyed Son of a Bitch.'"

How did Trump go from trying to help a Republican in a special election race to insulting an NBC anchor? And in a district that, though he won by 20 points in 2016, is now a swing district?

Well, the short answer is that everything is about Trump. To Trump, all the world is his stage and the rest of us are merely players. So, when Trump goes off script to appease his base by bashing the media, for example, it's because Trump is desperate to entertain.

In fact, he told his audience, "If I came like a stiff, you guys wouldn't come here tonight," echoing what he said on the campaign trail: "If I go too presidential, people are going to be very bored."

That's why In the middle of this rally, Trump bragged to the audience about his 1999 interview on "Meet the Press," where he declared we need to take the North Korean leader "out now."

Then Trump went on a tangent by turning to discuss the current host of "Meet the Press," Chuck Todd. Trump, for reasons only Trump knows, slammed Todd: "'Meet the Press,' a show now headed by sleepy-eyes Chuck Todd." He added the line that would become the sound bite of the night: "He is a sleepy son of a bitch, I'll tell you."

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Did Trump return to focusing on Saccone and providing detailed and compelling reasons to support him? Of course not. Instead Trump shared his views on everyone Trump related. He told the audience of his fantasy of running against Oprah Winfrey in 2020, declaring, "Wouldn't we love to run against Oprah? I would love it."

Then he slammed one his favorite targets, Sen. Elizabeth Warren, with his racist nickname for her, "Pocahontas." Trump also found time to demean a Democrat from California, Rep. Maxine Waters, who he stated is a "very low IQ individual." All this is Trump fulfilling his desperate and personal need to both entertain and be loved even if it comes at the expense of the GOP candidate he was there to endorse.

But Trump did take a shot at Saccone's 33-year-old opponent, Lamb , who is a former prosecutor and a veteran of the US Marine Corps, by sharing that he heard Lamb was "nice-looking." However, because Trump couldn't spend too long talking about someone other than himself, he told the crowd : "I think I'm better looking than him. I do. I do. I do." All that was missing was Trump then yelling out: "Live from New York, it's Saturday Night!"

Keep in mind the last person Trump offered a similar "endorsement speech" for was Republican Alabama Senate candidate Roy Moore. Just days before the Alabama special election, Trump held a rally on the Alabama-Florida border, where he endorsed Moore, but once again made a speech largely about himself. In fact, he spent the first part of his speech attacking the media for faulty reporting on him and his administration, before returning to the subject at hand, Moore. Moore lost the general election in a stunning upset to Democrat Doug Jones.

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In fact, since Trump took office, Democrats have flipped 39 state legislative seats from red to blue, the last two just a few weeks ago in special elections in New Hampshire and Connecticut. The Democrats -- for the most part -- can thank Trump for these wins. Trump is not only an unpopular president with an approval rating as low as 35%, but he's also a polarizing figure who inspires people to come out to vote against the GOP.

Come Tuesday, we may find that Trump's Saturday night rally may have actually helped the Democratic candidate there by mobilizing more of Trump's opponents to vote. But regardless of the outcome, in this district that Republicans have held a stranglehold on for nearly two decades , the fact that this race is so close is in large part because of the unpopularity of one person: Donald J. Trump.

And come November, Democrats may have that same Trump to thank if they do, in fact, see an electoral blue wave sweep them into power.