Are Barack Obama and John McCain Swapping Leads in the Race?

As my colleague Robert Schlesinger posted earlier today, one new major national presidential tracking poll shows Sen. John McCain beating Sen. Barack Obama by 5 points. This is the first time this political season I've seen Senator McCain in a national poll this far ahead.

As reported on the Zogby International website:

UTICA, New York—As Russian tanks rolled into the Republic of Georgia and the presidential candidates met over the weekend in the first joint issues forum of the fall campaign, the latest polling includes drama almost as compelling—Republican John McCain has taken a five-point lead over Democrat Barack Obama in the race for President, the latest Reuters/Zogby telephone survey shows.

But other polls still show Senator Obama ahead. Rasmussen Reports, Scott Rasmussen's firm, shows Obama ahead by 3, but when "leaners" are included, Obama is only 1 point ahead.True, this is a statistically insignificant difference, but odd given that Rasmussen is constantly accused of favoring Republican candidates. What does this tell you? I will not go near making a prediction about who's going to win this race. I've said all along it's going to be a squeaker and either candidate could take it. But part of me also says the Democrats took a huge risk nominating the most liberal member of the U.S. Senate (at least as categorized by the National Journal) instead of someone more moderate. No one could have successfully called Bill Clinton or Jimmy Carter "liberals" when they first ran for president. (That characterization might have changed for Clinton once he entered office, but his Arkansas record and his campaign made him appear to be a moderate Democrat.)What do you think?