It’s not just the Republican candidates bruising their brand with petulant infighting. With Bernie Sanders’ win in Wisconsin earlier this week, the feud between him and Hillary Clinton is picking up steam. During a rally at Temple University, Bernie Sanders went on the offensive (if you can call it that) in response to Clinton’s recent attacks on him.

Here’s Bernie: “She has been saying lately that she thinks I am quote-unquote not qualified to be president. Let me just say in response to Secretary Clinton, I don’t believe that she is qualified if she is through her super PAC taking tens of millions of dollars in special-interest money. I don’t think you are qualified if you get $15 million through Wall Street for your super PAC. I don’t think you are qualified if you have voted for the disastrous war in Iraq.”

It’s not often we say this, but he’s right to say that Clinton isn’t qualified to be president — though for entirely different reasons. Clinton is a sleazy politician, and when it comes to character her duplicitous behavior makes Sanders look like a saint. That said, if this is the best Sanders can muster, he’d better start packing up and heading home.

There are numerous better examples Sanders could have chosen. First of all, the Benghazi debacle that left four Americans, including a U.S. ambassador, dead on her watch. Then she lied repeatedly about it. That issue alone disqualifies her.

Or perhaps he could have mentioned the intensifying email scandal, and the pending FBI questioning of Clinton herself. Then there’s the pay-to-play income-tax shelter known as the Clinton Foundation, which we suppose he meant with is fundraising jab but didn’t actually name.

From a broader perspective, Sanders has to make sure he isn’t so strident in his criticisms that he can’t bring his supporters back around to her in the convention. Again, this is tame compared to the insults thrown on the GOP side, but the divisions are more stark now than at any previous point in the Democrat campaign. One thing is clear: If Sanders expects to derail the Clinton Machine, he’s got to do better than this.

(Revised.)