The first national poll (PDF file), taken by NBC and The Wall Street Journal after Sen. Barack Obama's historic speech, confirms that Obama essentially has defused the guilt-by-association attacks regarding his former pastor.

Here are the positive/negative ratings for the presidential candidates:

Sen. Barack Obama -- 49/32 (positive rating down 2 pts from two weeks ago)
Sen. John McCain -- 45/25 (down 2 pts)
Sen. Hillary Clinton -- 37/48 (down 8 points)

In head-to-head matchups versus McCain, Obama maintains his edge. Two weeks prior, Obama had a 3 point lead, and Clinton had a 2 point lead. Now, Obama has a 2 point lead, and Clinton is behind McCain by 2 points.

There are certainly some white Americans who were turned off by recent events: 35% of whites who saw Obama's speech were dissatisfied by it, and 46% said it "left uncertainties and doubts about his thinking and beliefs."

But according to MSNBC's Chuck Todd on Hardball tonight, Obama was hurt mainly among "southern, older, rural" voters, not where Obama was expecting to expand the electoral college map. Todd said Obama held his support among independents, and among voters in the Midwest and West.

On the whole, elevating the discourse helped Obama withstand several days of awful press. While the scorched earth tactics of the Clinton campaign are dragging her down.

(I don't think you can point to the Bosnia flap for these numbers, the poll was conducted a little too early to pick up any reaction to that.)

She may be maintaining her base of support within the Democratic party (the two are in a dead heat among primary voters), but that is not enough to wrest the nomination away from Obama. And she is doing nothing to broaden her support for a general election.

The "kitchen sink" strategy got her past Texas and Ohio, but now it appears she's paying the price for it.