McCain narrows Obama's lead in key states

[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2008/images/07/31/art.mccainstate.gi.jpg caption="McCain has narrowed Obama's lead in three key states."]

(CNN) - Barack Obama and John McCain are statistically tied in Florida and Ohio while Obama holds a clear advantage in Pennsylvania, new Quinnipiac polls out of those crucial battleground states Thursday show.

But in what could be a warning sign for Obama as voters begin to turn their attention to the general election race, Obama's lead appears to have dwindled, or barely remained steady, in all three states, even as the Democratic presidential candidate has enjoyed a wave of intense media coverage surrounding his trip abroad.

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In Florida, Obama now holds a statistically insignificant 2-point lead over McCain, 46-44 percent. In a similar poll taken one month ago, Obama held a wider, and statistically significant, 47-43 percent advantage over the Arizona senator there. The difference appears to be a shift among independent voters, who now support McCain in Florida by a 5-point margin. In the June poll, Obama held the advantage among the same group of voters by a 10-percent advantage.

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In Ohio, the battleground state where a weak economy should give Democrats an advantage, Obama is ahead by a 2-point margin, 46-44 percent. That lead, also statistically insignificant, is down from the 6-point advantage the Illinois senator held there one month ago.

Obama's lead has also narrowed in Pennsylvania, though he still enjoys a clear edge there. Obama now leads McCain by a 7-point advantage, 49-42 percent, down from the 11 point advantage he had in June.

The poll was conducted from July 23-29, in the midst of Obama's trip abroad, and carries a margin of error of just under 3 points in each state.