From Newsweek:

Sen. Hillary Clinton's primary victories in Texas, Ohio and Rhode Island have revived her near-dead campaign and brought her into a statistical dead heat with Sen. Barack Obama among registered Democrats and Democratic leaners, according to a new national NEWSWEEK Poll...

Obama is the favored nominee among 45 percent of Democrats, compared with 44 percent for Clinton, according to the poll, which was based on telephone interviews with 1,215 registered voters March 5-6.

The controversial 3 A.M. ad may have helped, Newsweek sez, but the poll also suggests that it's unclear how much the "commander in chief threshold" that Hillary keeps talking about will matter in the long run...

[The poll] suggested that Clinton's ominous "3 a.m. phone call" ad benefited her campaign. Almost half (45 percent) of Democrats said they would trust Clinton to answer the red phone in the wee hours, while only a third felt that way about Obama. Similarly, on the issue of national security, almost half (47 percent) of the Democratic base said that they trust Clinton to protect the country; only a third feel the same about Obama.

But it's not clear how much these sentiments will matter at the ballot box: just 4 percent of Democrats overall, and 4 percent of Clinton's supporters, name terrorism as their top issue.

And the poll also contains a key stat for Obama: She is still far more polarizing than he. Forty percent of registered voters view her unfavorably, while 35% have that view of McCain and only 28 percent view Obama unfavorably.