Earlier this month I noted the growing Democratic refrain that Hillary Clinton and the Democratic Party would both benefit from Hillary having some real competition for the nomination in 2016. For Hillary, she could test out her responses to various lines of questioning and sharpen her debating skills. For Democrats, they’d get a better nominee or possibly even a different nominee if something emerged to knock Hillary from the race. (Better in the primaries than in the general.) I also noted that former Maryland Governor Martin O’Malley did not seem to be auditioning for the role of genuine rival. But maybe that’s changing.

On Sunday’s This Week, O’Malley took a couple shots at the Democratic frontrunner:

“Let’s be honest here,” O’Malley said. “The presidency of the United States is not some crown to be passed between two families.”

O’Malley also hinted that a Clinton nomination is not a sure thing, possibly alluding to the 2008 primary, when she was also thought to have had it locked down.

“History is full of times when the inevitable frontrunner is inevitable right up until he or she is no longer inevitable,” he said.

Yet as Jesse Walker notes, not only did O’Malley not name Hillary, he demurred when pressed and spoke in generalities about the campaign. “This just isn’t the way an insurgent candidate talks,” Walker wrote.

Isn’t it? I’m not convinced this wasn’t O’Malley’s own timid, slightly goofy way of trying to dispel the notion that he’s the Mikhail Prokhorov of Clinton’s coronation. We’ll find out soon enough, I suppose, but I think the subject of O’Malley’s comment is telling.

There are two kinds of criticism of Hillary Clinton from her fellow Democrats. The first is issue-based, designed to portray Clinton as out of touch with the party’s true political identity. For example, Bernie Sanders, the Vermont socialist, may run in the Democratic primary as a way to trumpet the issue of inequality. “Today, in my view, the most serious problem we face as a nation is the grotesque and growing level of wealth and income inequality,” Sanders told the Brookings Institution last month. “This is a profound moral issue. It is an economic issue, and it is a political issue.”

Bernie Sanders, like most of the potential Democratic candidates, does not pose a serious threat to Hillary’s chances. But Clinton is simply not a credible advocate of the kind of economic-justice policies the far left would like to see. Not only is she too close to Wall Street for the redistributive left, but the entire raison d’être of her current career appears to be to massively increase the amount of money in politics, including from foreign (and deeply illiberal) sources. Hillary’s fine with Sanders’s candidacy, because she’ll always look like a more serious Democrat when running against an actual socialist.

There is, as we’re reminded endlessly, a more threatening version of a populist candidacy: that of Elizabeth Warren, who could actually beat Hillary. But Warren does not seem any closer to actually running today than she was yesterday or the day before, so the smart money’s on Hillary avoiding this particular trap.

Another issue-based critique of Hillary from the left will be her hawkishness. Clinton is a liberal interventionist, a proponent of the kind of light-footprint military intervention we saw in Libya. She is also more open to humanitarian missions than Barack Obama is, and she knows she’s somewhat vulnerable on matters of war and peace because that’s precisely the contrast Obama was able to draw in 2008.

But she wouldn’t be running against Obama. She might be running instead against former Virginia Senator Jim Webb. When he announced his exploratory committee, he said the U.S. must “redefine and strengthen our national security obligations, while at the same time reducing ill-considered foreign ventures.” It’s the sort of broad platitude he repeats from time to time, and it won’t harm Hillary.

Even Webb’s supporters are (for the most part) realistic about this. “Jim Webb, I acknowledge, is probably not going to become our next president,” wrote the Nation’s William Greider. “But he has the possibility of becoming a pivotal messenger.” And Hillary’s just fine with that: any candidate who makes her look more like a centrist without actually threatening her chances to win the nomination, and therefore doesn’t force her to her left during the primaries, is more of a help than a hindrance anyway.

But there’s a second kind of Clinton critique: one that has less to do with policy and more about character. And this one can potentially hurt Hillary even coming from someone who won’t defeat her in the primaries. That’s because the kinds of stories that stick are ones that conform to a preexisting narrative, unfair as it often is. Hillary is nearing the end of her career, which means her public persona is close to set in stone–no matter how many different ways she programs herself to laugh.

Had O’Malley kept his criticism to economic policy or even climate change, it would have been unexceptional. But pointing out Hillary’s sense of personal entitlement and her family’s stature as American royalty risks reminding even some Democrats that they don’t really like the idea of Hillary’s candidacy as much as they’d like to, even if they like her personally.

So is the key takeaway from O’Malley’s comments that he refused to use Hillary’s name–or that he didn’t have to? It’s a distinction that may tell us more about whether he’s really willing to take on the Clintons, or merely aiming to share in the spoils of what he hopes is her eventual victory.