Is it too soon to say that Mitt Romney’s attack on Obama’s “didn’t build that” speech — which was supposed to be a game-changer — is officially a bust?

That’s not a rhetorical question. I’m genuinely interested in whether there’s a way to gauge the answer. The two national polls released yesterday — which both find significant leads for Obama — show no signs whatsoever that this attack line has had any impact.

The goal of this attack — combined with Romney’s assault on Obama’s “it worked” quote and Romney’s claim that Obama wants to send “welfare checks” to people who don’t work — is to cast the President as out of touch with the struggles of ordinary Americans. The attacks also about suggesting he’s hostile to the hard work of the middle class and wants to shift their hard earned money into building a redistributionist government-centric society, directing middle class resentment downwards.

Yet the new CNN poll finds there has been a slightly upward movement in the number who think Obama favors the middle class over the rich or poor. A plurality, 42 percent, say this about Obama; pluralties of independents (42) and moderates (48) say the same. Smaller minorities of both groups say he favors the poor.

By contrast, pluralities of Tea Partyers (47) and of conservatives (44) say Obama favors the poor — a suggestion that this attack line is resonating mainly with the base, which may be its primary goal.

Meanwhile, a solid majority, 64 percent, say Romney favors the rich; 68 percent of independents and 74 percent of moderates say the same — meaning Obama’s class-based attack on Bain, tax returns and offshore accounts may be faring better than Romney’s class-based assault.

Meanwhile, in the new Fox News poll, Obama has his highest favorable rating in more than a year, while Romney’s favorable rating has dropped six since last month and his unfavorable numbers have gone up five. And the recent round of NYT/CBS swing state polls found Obama faring far better than Romney on the question of who understands the needs and problems of ordinary people.

It needs to be said that the Obama campaign has taken these attacks very seriously, and it’s admittedly very hard to gauge the impact this stuff is having on both sides. We won’t really know whether they are or aren’t working until closer to the election, when undecided or weakly committed voters begin seriously making up their minds, based on impressions built up over months. But if the primary attacks Romney has waged for weeks now are having an impact, it has yet to show up in polls.