by Mark Silva

It's a safe bet that either Hillary Clinton or Barack Obama could fare well this year in states where the Democratic presidential nominee had a comfortable lead in 2004, and that John McCain can perform similarly in comfortably Republican-voting states.

But in the competitive middle-ground - what some like to call "the purple states'' - who might hold the advantage in November? As it stands now, with a survey of polling throughout the past month, Gallup reports that the Democrats hold the edge in those battlegrounds.

Obama holds a four-point advantage over presumptive Republican nominee McCain among registered voters in states that were competitive in the 2004 election, Gallup reports, based on an aggregate of more than 13,000 interviews with voters nationwide in Gallup's daily tracking polling so far in April.

Clinton also holds a four-point advantage over McCain in these states, Gallup reports - but this part is noteworthy: "She does not fare quite as well as Obama does in blue states, and she trails McCain by a slightly larger margin than Obama does in red states,'' Gallup's Jeff Jones reports.

The states in question: New Hampshire, Pennsylvania, Ohio, Michigan, Wisconsin, Minnesota, Iowa, Florida, Colorado, Nevada, New Mexico, and Oregon - where 31 percent of the nation's voters reside.

McCain 'can take solace'' that there are more red states, more voters, and thus, more electoral votes in those states,'' Jones notes. "So even though he trails by four points in the most competitive states, he is down by only two points to Obama (46 to 44 percent nationwide).''

"According to 2004 election statistics: 36 percent of all voters in that election resided in red states, 33 percent lived in blue states, and 31 percent in purple states,'' Jones notes. "So the Democratic candidate is starting out at a disadvantage, everything else being equal.

"Thus, in order to win the election, the Democratic candidate probably has to defeat the Republican by at least a couple of percentage points in the competitive states, assuming the vote distributions in the red and blue states stay relatively constant,'' he adds. "The Republican can probably win by essentially breaking even in the competitive states, as Bush did in 2004.

"It's likely that the 2008 election will be fought in the battleground states, just as in prior elections. Gallup's election polling to date suggests that the presidential election could be very close, because neither McCain nor his Democratic rivals have maintained much of a lead in recent weeks..

"As of now, Obama and Clinton have an advantage over McCain among voters in the competitive states,'' Jones concludes. "Given that more states fall into the Republican column than into the Democratic column, the Democratic nominee probably needs to maintain that advantage in order to prevail in enough purple states to gain the electoral vote advantage in November.''

The findings are based on telephone interviews with 13,217 registered voters conducted April 1-15, 2008. The overall national findings have a possible margin of error of just one percentage point.

For results based on the sample of 4,894 registered voters residing in states that George Bush won in 2004, the possible error is two percentage points. For results based on the sample of 4,375 registered voters residing in states that John Kerry won in 2004, it's also two percentage points. And for results based on the sample of 3,948 registered voters residing in states where the margin of victory for the winning candidate in the 2004 presidential voting was five percentage points or less, two points.