There's less of a split, though, on the Obama campaign's association with the community group ACORN; 49 percent say it's not a legitimate issue, 40 percent say it is, with more, 11 percent, unready to express an opinion on the subject. McCain's accused ACORN of voter registration fraud; the group blames some of its canvassers for filling out faked forms, and says it itself has notified the authorities of such cases.
On the vice presidential candidates, 52 percent of likely voters say McCain's pick of Palin has made them less confident in the kind of decisions he'd make as president; that's up 13 points since just after the selection, as doubts about Palin's qualifications (also voiced by Powell on Sunday) have grown. Just 38 percent say it makes them more confident in McCain's judgment, down 12 points.
Those numbers are more than reversed on Obama's pick of Joe Biden: 56 percent of likely voters say it makes them more confident in Obama's decision-making, 31 percent less so.
Optimism, meanwhile, is a strong point of differentiation between the two candidates. Likely voters by 62 percent to 30 percent see Obama as more optimistic than McCain - all else equal, an attractive quality in a candidate, as Ronald Reagan demonstrated. And in a similar attribute, voters by a 17-point margin, 54-37 percent, see Obama has having the better personality and temperament for office.
INDIES - On all these, the views of swing-voting independents are critical. They see Obama as more optimistic by 57-31 percent and as better-suited temperamentally by 52-36 percent. The Palin pick makes them less rather than more confident in McCain's judgment by 51-39 percent, while the Biden selection makes them more rather than less confident in Obama by 50-33 percent.
Independents by 60-37 percent say Ayers is not a legitimate issue; on ACORN they divide more narrowly, 47-42 percent.
OTHERS - There are other differences among groups. Views of the Palin selection, naturally, are highly partisan. But majorities of moderates (62 percent), young adults (59 percent) and women (56 percent) all say it makes them less confident in McCain's judgment. (More women than men say so.) So do near majorities, 48 percent, of white women and married women alike.
The pick plays better in the GOP base: 70 of Republicans, 68 percent of evangelical white Protestants and 67 percent of conservatives say the selection of Palin makes them more confident in McCain's decision-making.
On Ayers, similarly, 62 percent of conservatives and 67 percent of Republicans say it's a legitimate issue. Just 29 percent of moderates, 12 percent of liberals and 10 percent of Democrats agree.
METHODOLOGY: This ABC News/Washington Post poll was conducted by telephone Oct. 16-18, 2008, among a random national sample of 995 likely voters, including landline and cell-phone-only respondents. Results have a 3-point error margin for the full sample. Sampling, data collection and tabulation by TNS of Horsham, Pa.