National Republicans and conservative groups have made Elizabeth Warren the number one target of one of their leading attack strategies: Seizing Occupy Wall Street’s excesses to discredit Democrats and the larger populist message they’ve adopted in the wake of resurgent public concern about inequality.

The Rove-founded group Crossroads GPS has run ads falsely insuinating that Warren backs the violence of protesters, and national Republicans have called on her to repudiate the protests. Warren has mostly refrained from taking the bait, instead keeping the focus on Wall Street and arguing that concerns about inequality and Wall Street unaccountability are mainstream.

A new poll just out from the University of Massachusetts suggests this conservative line of attack has yet to bear fruit.

The poll finds that Warren has edged ahead of Scott Brown among registered Massachusetts voters, 43-39, though that’s within the margin of error. What’s more interesting is what the internals tell us about whether each side’s message is resonating. For instance:

Warren’s candidacy appears to resonate strongly among lower and middle class voters. Respondents earning $40,000-$100,000 support Warren by 11 points (48 percent to 37 percent), while those making less than $40,000 support her by of 15 points (42 percent to 27 percent).

This, despite the fact that the primary target of efforts to link Warren to Occupy Wall Street are working class whites from places like south Boston who (the theory goes) should be culturally alienated by Warren’s embrace of the protests. A caveat: Brown does hold a double digit lead among independents, and is seen as more moderate than Warren, both of which could be pivotal. The poll is also evenly tied on views of the protests.

Perhaps more important, Warren holds the edge on which candidate is trusted more on the economy (38-32) and even taxes (37-30). This, despite the effort to paint Warren as, alternately, a wild-eyed radical foe of the free market and a snooty liberal elitist who thinks she knows far better than working folks how their money should be spent. Perhaps Massachusetts voters don’t find the message expressed in that viral video — that it’s fair to ask the wealthy to pay a bit more in taxes to keep the society that helped them get rich functioning smoothly — to be so radical after all.

UPDATE: This is an online poll, and there’s a debate underway among public opinion research professionals as to whether such polls are comparable to polls based in scientific sampling theory. But YouGov is considered by some professionals to be better than most other online pollsters at weighting samples to make them predictive and accurate.