WASHINGTON — The presidential race remains volatile and unpredictable, largely because of a huge bloc of undecided swing voters.
"The middle of the electorate is reasserting itself in this election," according to a Pew Research Center survey released Thursday.
Among all voters, Democrat Barack Obama leads Republican John McCain by 48 to 40 percent. Pew polled 2,004 people by land line and cell phone from June 18 to 29. The margin of error is plus or minus 2.5 percentage points.
The White House hopefuls face an unusual number of variables, and as a result "the outlook for the presidential election in midyear is substantially different than at comparable points in time in recent campaigns," the survey found.
Among those variables:
- Independents make up about one-third of the electorate, and those who have preferences are split virtually evenly between Obama and McCain, with 42 percent for Obama and 41 percent for McCain.
- Both candidates "face formidable challenges in consolidating their bases." McCain has "an enthusiasm problem" among Republicans, while Obama "has a unity problem" among Democrats.
- Turnout is likely to be far higher than in previous recent elections.
- Domestic issues are foremost on voters' minds.
However, some 46 percent of independents are undecided or only lukewarm toward their current choices. Only 28 percent of them said they'd certainly vote for Obama, while only 26 percent said they were sure to back McCain.
Pew also discussed swing voters, who include the undecided and lukewarm independents as well as registered Republicans and Democrats who say they could vote for the other party's choice. One-fourth of conservative Republicans now are considered swing voters.
The swing voters mirrored the rest of the country demographically in age, gender and stands on issues.
Slightly more than half said that Obama could connect better with ordinary Americans, but a slight majority also said that McCain was more likely to use good judgment in a crisis.
Thirty-seven percent said McCain "shares their values," while only 25 percent said that about Obama. The chief concern of swing voters was the economy, followed by Iraq, then energy concerns.
McCain has the bigger hurdle, however. Pew found that he "receives far less strong backing from his supporters." Only 35 percent of McCain's supporters say they back him strongly, while 55 percent of Obama's voice strong support for him.
A sizable majority of McCain backers said that the phrase "has new ideas" better applies to Obama.
McCain also hasn't been enthusiastically embraced by white Protestant evangelicals. He's the choice of 61 percent of them, but that's down 8 percentage points from President's Bush June 2004 showing.
Though Obama is slowly gaining support among backers of Hillary Clinton, his former rival, problems remain, as he has the backing of only 69 percent of her loyalists. Only 35 percent of them said he was "personally qualified," while 43 percent said McCain was.
Voter interest, particularly among Democrats, continues at high levels. Younger people in particular are more interested than usual. Pew that found two-thirds of 18- to 29-year-olds have given "quite a lot of thought" to the election, up from 53 percent four years ago and 35 percent in June 2000.
Interest was up among all age groups. Some 63 percent of all voters told Pew that they were "more interested in politics" than in 2004, and nearly three in four said they were giving a lot of thought to the election, also well above the level of four years ago.
That may be good news for Democrats, whose level of engagement this year is well above that of Republicans.
Some 71 percent of Democrats said they were more interested in the election than they were four years ago, compared with 51 percent of Republicans. The 20 percentage point gap is far higher than in 2004, when Democrats were only slightly more interested.
Some 44 percent said they most wanted candidates to discuss the economy, with Iraq a distant second priority at 19 percent.
But Pew found that "a growing number cites energy as the issue they most want to hear the candidates discuss," as it was mentioned by 17 percent of voters, up from 7 percent in April. Health care was fourth, at 9 percent.
Interest in the economy and energy was uniform: Equal numbers of Democrats, Republicans and independents said it was of paramount importance.