WASHINGTON - Two recent national polls showed one of the presidential candidates moving ahead of the other.
They just couldn't agree on which one.
A Pew Research Center survey of likely voters conducted Oct. 4 to Oct. 7 gave Republican nominee Mitt Romney a four- percentage point lead over President Barack Obama. A Gallup poll of registered voters Oct. 1 to Oct. 7 showed Obama advancing over Romney by five points one day after, in a shorter tracking survey of three days immediately following their Oct. 3 debate, it called the race a tie.
The conflicting results underscore the lack of clarity in an environment in which, almost every day, new polls are released that vary depending on how voters are contacted, how they are counted and other variables tied to an individual polling group's approach to conducting surveys.
Both Democratic and Republican pollsters have a general sense that Romney's support has grown and Obama's slipped since the former Massachusetts governor's performance in last week's first presidential debate in Denver. There's little consensus, though, on how deep or enduring that change in the race's dynamic may be.
"Romney clearly has gotten a boost coming out of the debate and it's for obvious reasons," said Whit Ayres, a Republican pollster who's worked on several presidential and congressional campaigns and is part of National Public Radio's bipartisan polling team.
Even so, Ayres said he's looking for more of a pattern that shows Romney closing a gap with Obama before pronouncing that the gains are lasting ones.
Peter Hart, a longtime Democratic pollster who has run surveys for the Wall Street Journal and NBC News, agreed. "Romney has been helped" by his debate performance. Yet "a pattern is a series of results showing something in the same direction," he said. "It's just too few polls and too few days."
Romney's improved standing in some polls conducted since the debate has "added an exciting twist because things were moving in one direction," toward Obama, said J. Ann Selzer, an Iowa-based pollster who conducts surveys for Bloomberg News.
Still, conflicting results also have only emerged in polling of the states both campaigns say will decide the election.
In Colorado, Selzer conducted a poll for the University of Denver of likely voters from Oct. 4-5 that gave Obama a four- point lead, 47 percent to 43 percent. Rasmussen Reports had Obama ahead, 49 percent to 48 percent, among likely voters surveyed Oct. 7.
Rasmussen Reports, which Ayres said "tends to lean more Republican in the makeup of its sample," had Romney leading in Virginia, 49 percent to 48 percent, according to an Oct. 4 poll of likely voters. The firm uses a technique, questioned by some nonpartisan polling experts, called robo-calling, which relies on automated phone surveys that require participants to respond using dial pads.
A Democratic-aligned firm, Public Policy Polling, uses the same robo-calling technique and put Obama ahead by three points in Virginia, 50 percent to 47 percent, according to its Oct. 4-7 poll of likely voters.
Both Democratic and Republican pollsters express concern that groups using robo-calling may fall short in adequately screening voters to verify their identity, in reaching cell phone users who tend to be younger and Democratic-leaning, and in providing enough transparency to confirm their sampling populations are balanced to reflect the makeup of the general population.