WASHINGTON -- With attention turning to the first of three upcoming national debates, new polls show President Barack Obama continuing to hold a narrow lead over Republican nominee Mitt Romney, both nationwide and in the key battleground states that are likely to decide the election.
Two new national surveys released on Monday morning both show a slightly closer race than most other recent polls, although those new results are consistent with previous surveys from the same organizations, indicating that Obama's September lead is holding.
The new Washington Post/ABC News survey finds Obama leading by just 2 percentage points nationwide (49 percent to 47 percent) among the voters deemed most likely to vote. But that result was no different than their previous survey, taken just after the Democratic convention three weeks ago, which showed Obama with a 1-point edge (49 percent to 48 percent).
However, among all registered voters nationwide, the new Post/ABC poll shows Obama leading by 5 percentage points (49 percent to 44 percent), again the same margin as their survey found three weeks ago. The Post also reports that Obama's lead over Romney is larger (52 percent to 41 percent) among a subset of likely voters in swing states.
Similarly, a new Politico/George Washington University Battleground poll also finds Obama leading by 2 percentage points among likely voters (49 percent to 47 percent), a finding essentially unchanged from the 3-point Obama margin (50 percent to 47 percent) found in their previous survey.
The four results have been collectively more favorable to Romney than those produced by other recent national polls, and more importantly, they have shown no statistically meaningful trend in September. The HuffPost Pollster tracking model, which draws on all national and state-level polling and corrects for consistent "house effect" differences among pollsters, continues to give Obama a slightly larger, 4 percentage point lead over Romney.
Similarly, a handful of new statewide surveys released over the weekend shows results consistent with a 3- to 4-point Obama lead nationwide.
In Ohio, an automated recorded-voice survey by the Democratic-affiliated firm Public Policy Polling gives Obama a 4 percentage point advantage, while a new Columbus Dispatch mail-in survey gives Obama a 9-point lead. Not surprisingly, Obama's lead on the Pollster tracking model falls somewhere in between.
Finally, another new PPP poll from North Carolina shows a dead-even race, with each candidate at 48 percent -- again, consistent with a similarly close margin on HuffPost's tracking model. North Carolina has been the closest of the 50 states over the last three weeks.
Thus, the combination of national and statewide polling continues to show Obama leading Romney by statistically meaningful margins in all of the battleground states except North Carolina. Were he to carry all of the states where he is currently leading, Obama would win 332 electoral votes -- far more than the 270 needed to win. Romney currently leads in states accounting for 191 electoral votes.
Can Wednesday night's nationally televised debates between Obama and Romney, the first of three to be held between now and late October, be a "game changer" for Romney? Not likely, according to George Washington University political scientist John Sides.
"When it comes to shifting enough votes to decide the outcome of the election," Sides writes in the Washington Monthly, "presidential debates have rarely, if ever, mattered."
Sides cites research by political scientists Robert Erikson and Christopher Wlezien, who studied polling from every election from 1952 to 2008 and found that while debates sometimes nudge results, they rarely produce substantial changes in voter preferences. Erikson and Wlezien found that since 1960, the leader in the polling before the debates remained the leader after the debates.
The most significant before-and-after debate shift was toward Gerald Ford in his 1976 race against Jimmy Carter. However, as Erikson and Wlezien note, "Carter's support was in steady decline" during the final month of the race.
It is worth remembering that while Obama enjoys a statistically meaningful lead in national polling, his margin remains relatively modest compared to past elections. So while a "nudge" toward Romney on the order of what debates produced in 1980, 2000 or 2004 might not be enough to move Romney ahead, it could make for a much closer race.
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