Low-key one of my favorite subplots of the Democratic primary. Watch this new ad from Bloomberg — not the first one this month to prominently feature Barack Obama, mind you — then read on.

I don’t come away from that concluding that Obama has endorsed Bloomberg. You probably don’t either. It looks a lot, in fact, like the ad that Joe Biden ran featuring old A/V of Obama at the start of the primary, and of course Obama famously hasn’t endorsed Joe. But you and I watch a lot of political ads relative to the average person and might be more attuned to nuances in the message. Imagine if you haven’t watched many and you hear this come on your TV in the background while you’re busy doing something at home. Or better yet, you hear the radio version of it that doesn’t make clear when Obama’s warm words about Bloomberg were uttered (i.e. not recently).

What conclusion might you draw?

An erroneous conclusion, but one that’s very, very useful to Mike Bloomberg’s candidacy.

Need more evidence that “Wait, Obama endorsed Bloomberg?” is very much a thing? No problem:

South Carolina political analyst Bakari Sellers says he hears all the time from voters of color intrigued by Bloomberg’s ads — especially one that features an old audio clip of former president Barack Obama praising Bloomberg. “I’ve had so many people ask me ‘Why did Barack Obama endorse Mike Bloomberg?’ ” he said, frustrated. (Obama hasn’t endorsed anyone.)

It’s not just random joes who are fooled either. David Axelrod told the WSJ a few days ago that he’s had “numerous calls” from “political operatives and some elected officials” asking if Obama had endorsed Bloomberg. In reality, Bloomy and O were never close political allies. They were aligned on gun control and climate change but Bloomberg didn’t endorse him in 2008 and only finally endorsed him in 2012 towards the end of the campaign. He called ObamaCare a “disgrace” in 2010 on grounds that it didn’t do nearly enough to address the health-care problems Obama had identified in championing the program. Read the Journal piece and you’ll find a series of other disagreements between the two, from foreign policy to financial reform to Bloomberg’s dim view of how Obama got elected. (“People used to say he’s so wonderful and he gave a great convention speech four years before he got elected.”)

ObamaWorld isn’t thrilled, and now has to balance their annoyance against the fact that Bloomy’s the last best chance for their brand of neoliberalism to overcome Bernie Sanders:

[S]ome of Obama’s closest, and oldest, political associates have bristled at the way Bloomberg’s ads have framed them as longtime allies. In recent days, some have been rehashing how Bloomberg appeared with both Obama and John McCain in 2008 — calling the then-senator not experienced enough to be president at the time — and how he only endorsed Obama over Mitt Romney at the very end of the 2012 race. A Friday evening HuffPost report revealing that in 2016, Bloomberg appeared to lay some blame for racial divisions in the country with Obama didn’t help, nor did a Sunday CNN story detailing how Bloomberg called Obamacare a “disgrace” in 2010.

Biden, for one, shared his displeasure at a fundraiser just off of Central Park South on Thursday: “The advertising I’ve seen, you’d think that Mike was Barack’s vice president,” he told donors. Obama’s former campaign manager David Plouffe chimed in on Friday morning: “The power of saturation advertising,” he tweeted. “Someone at my gym in California asked me why Obama chose Bloomberg over the rest of the field.”

How much of Bloomy’s polling surge is due to the false impression that he’s been endorsed by Obama? And to the extent that that impression has been made, how easily can it be undone? Biden’s going to shred him at the debate tomorrow night over this, wanting to reclaim Obama’s legacy for himself as South Carolina and Super Tuesday approach. But maybe O’s comments about Bloomberg in the ad are sufficient in themselves to negate Biden’s criticism. He is praising Bloomberg in those old clips even if he’s not endorsing him, after all. Besides, this is a fraught subject for Biden: If he accuses Bloomberg of trading on Obama’s name despite not having received O’s endorsement, Bloomberg can attack by pointing out that the same is true of Biden. Why is it, Joe, that the former president has been so reluctant to support your candidacy even though his signal legislative achievement, ObamaCare, is at risk from Bernie Sanders and Elizabeth Warren? Is it because he lacks confidence in your ability to win this nomination from a better-funded candidate with more enthusiastic support?

What does Biden say to that?

Exit question: When’s Bernie going to start running his own disingenuous “Obama likes me best” ad? There must be footage over the course of eight years of O saying some politely complimentary things about him.