One never knows what one might overhear while traveling the infamous 'Acela corridor' between Washington, DC and Boston. Sometimes it's a former top spy giving an off-the-record interview in earshot of fellow passengers. Sometimes it's a well-connected political operative loudly spouting off about a sitting Vice President's potential entry into the presidential race. And sometimes it's a well-known Clinton ally indiscreetly assessing the state of Hillary Clinton's campaign, savaging her critics and opponents with unguarded candor. To be clear, this individual and his two traveling companions were speaking openly and loudly in public. Listening to their conversation required no strain; anyone in the immediate vicinity could clearly hear what was being said -- including at least one other reporter. A few highlights from this morning's nearly half hour-long rant, which offers an intriguing window into Clintonworld's thinking:- This Clintonista trained much of his rhetorical fire on the mainstream media, which he believes has been grossly unfair to Hillary. He lamented what he sees as "ridiculous" double-standards, intimating heavily that sexism has played a role in the unjust coverage. On this point, he complained that some commentators' penchant for referring to Hillary as "shrill" is comparable to using an ethnic slur to describe a politician of color. "Strident" would be more neutral, he concluded. He was especially agitated by the email scandal, which he views as a "stupid" obsession. One of his traveling companions evinced shock at how often she's asked about the issue.- The Vermont Senator who's steadily gained on Mrs. Clinton in Democratic primary polls is "sanctimonious" and a "flip-flopper," the Clinton confidante intoned, incredulously adding that Sanders is "a Socialist" who can't win. "There's no way he can be nominated -- ever," he said. A younger associate traveling with the prominent operative called Sanders "a nut."- Special frustration was reserved for the Vice President, whom this individual believes will "absolutely" jump into the race. "Memories are short" regarding Joe Biden, he said, admonishing his travel buddies to remember that Biden has long been seen as a "buffoon." The Vice President enjoys near-universal name recognition, Clinton's pal continued, yet he trails both Clinton and Sanders in public polling -- an indication of Biden's weakness, he said. When another colleague pushed back, noting that Biden isn't an announced candidate yet, the long-time Clintonista dismissed her point: Hypothetical candidates are often more popular than actual candidates, he cautioned. Why isn't Biden at least beating Sanders? "He's in third place!" Despite his occasional bravado, the politico did express concerns that Biden could siphon votes off from Hillary, boosting Sanders' chances -- but ultimately expressed confidence that Hillary remains in a strong position: She's still "20 points ahead," despite her polls hitting what he characterized as "the bottom of the bottom." Biden's numbers will fall as soon as he enters the race, the chatty strategist opined, complaining that the pro-Biden "media isn't talking about that."- Discussing next week's first Democratic debate, he projected total confidence: "She's so good," he crowed, anticipating that Mrs. Clinton would outclass the rest of the field. He argued that the former Secretary of State should aggressively attack the NRA and parlay her criticisms into an an exposure of Sanders' pro-gun record. "The NRA has endorsed him! He was against background checks!" He laughed off Sanders' recent backtracking as nakedly political, for which the insurgent candidate has offered "stupid" explanations. Sanders is "so sanctimonious, but he's a flip-flopper," he scoffed. They discussed whether Clinton should "get emotional" on the issue, with the politico suggesting that it could "work with women." On a separate issue, if Sanders presses Clinton on her deep ties to Wall Street , this operative suggested that Hillary highlight her new regulatory crack-down plan and ask Sanders, "what have you ever done on [reining in] Wall Street, besides rhetoric? Nothing." He said he expects Hillary to "slaughter" Sanders in the upcoming face-to-face forum.-- These were the only two Republicans name-checked over the course of today's harangue. Trump was treated as an amusing, if boorish, sideshow ("awful"); Fiorina, however, has clearly crawled under this Clintonite's skin. The way Fiorina criticizes Hillary is "so nasty, it's just…nasty," he fumed, before proudly pointing out that he employed a gender-neutral descriptor to criticize the former HP executive.- I discussed this on 'Outnumbered' this afternoon:As I said, another reporter was present for this, and she's naming names