While Barack Obama runs dead even with John McCain in a new Newsweek poll at 46 percent each with 8 percent undecided, the survey took a hard look at the race factor by employing what it called a “Racial Resentment Index” to further analyze voting blocs and it concluded that, “Obama’s race may well explain his difficulty in winning over white voters.” (Click here to read the poll results and here to read the story).

Questions in the poll that tested voters on issues that involved race included views on affirmative action, whether blacks or whites lost out more because of racial preferences in things like hiring or school admissions, whether racial discrimination or personal responsibility accounted for problems facing black Americans, opinions on interracial marriage and dating and reaction that white voters would have if a black American with equal education and income moved into their neighborhood.

The survey was conducted May 21-22 and has a 3.5 percent margin of error for all registered voters and a 5 percent margin of error for registered Democrats and Democratic “leaners.”

McCain leads Obama among white voters 52 percent to 40 percent, which is offset by Obama’s big 68 percent to 25 percent advantage among non-whites. McCain’s lead among white voters over Hillary Clinton was only 48 percent to 44 percent. (In an overall match-up, she led him 48 to 44 percent with 8 percent undecided).

When broken down by Democratic voters who Newsweek identified as scoring high on its Racial Resentment Index, Obama led McCain 55 percent to 33 percent in contrast to Clinton who ran away from McCain by 77 percent to 18 percent. Among Democratic voters who did not score high on the Racial Resentment Index, Obama and Clinton both had leads over McCain of better than 4-to-1.

White Democrats with high RRI scores favored Clinton for the nomination by 67 percent to 21 percent while those with low scores tilted towards Obama 48 percent to 43 percent.

Obama was viewed favorably among overall voters by 54 percent to 40 percent, Clinton by 53 percent to 40 percent and McCain by 54 percent to 40 percent. McCain’s favorability ratings among white voters eclipsed Obama and McCain. He got positive marks from 60 percent of whites compared to 50 percent for Clinton and 49 percent for Obama.

In general, voters said the U.S. was ready for an African-American president by a 73 percent to 20 percent margin, and that view was supported by a similar margin among all white voters. However, breaking the white vote down by the poll’s RRI, voters who scored high on the resentment index supported that view by only a 54 percent to 53 percent margin compared to low-scorers who believed that by 80 percent to 12 percent.