It's clear why Trump has no problem ripping that piece of paper to shreds, Fix Boss Chris Cillizza notes: He got where he is now in the race with hardly any help from the Republican Party establishment, so he has nothing to lose if he walks away from his promise now.

That his two challengers are reacting similarly suggest they might feel the same way about the Republican Party. The establishment has proved pretty helpless in stopping Trump, so it's every man for himself out there.

Who is Corey Lewandowski, Trump's campaign manager?

(Joe Raedle/Getty Images)

Political operatives -- the ones telling the politicians what to say or do -- are typically people who prefer the shadows over the spotlight. Whether he likes it or not, Trump's campaign manager is now part of the story after Florida police charged him with battery Tuesday. The Post's Karen Tumulty delved into Trump's right-hand man and found these tidbits:

-In personal style and background, the two couldn't be more different, writes Tumulty: "One is a blustery celebrity billionaire whose hairstyle is a marvel of engineering and styling products; the other, an intense political operative who grew up in a blue-collar Massachusetts mill town and sports a no-fuss buzz cut."

-In political style, they might be a perfect match: "Both hit hard, play close to the lines — and occasionally step over them, disregarding the foul calls."

Why the media has done its job on Trump -- and why it may not matter

No surprise: After Trump's most recent drama, the did-the-media-help-create-Trump argument is back. New York Times columnist Nicholas Kristof apologized in a recent column for doing just that.

We respectfully disagree. The media, including The Washington Post, has aggressively fact-checked his comments, aggressively covered his less-savory antics and aggressively investigated his business dealings. We've done all we can and should be doing to cover Trump fairly, says Boss Cillizza. What voters do with that is out of our hands.

We in the media can fact check Donald Trump to death. We can extensively cover the charges of battery against his campaign manager for his treatment of a reporter. We can write about Trump retweeting white supremacists or unflattering pictures of an opponent's wife.What we cannot do is make people who support Trump (a) read that work or (b) have it factor into their decision-making processes.

We'll see you all Friday, for what we're sure will be yet another unpredictable day in the 2016 presidential campaign.

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