First-time voters underscore Barack Obama's organizational advantage in the presidential election: Four years ago first-timers backed Democratic nominee John Kerry by 7 points. Today they favor Obama over John McCain by 47.
Indeed it's first-timers who give Obama his clear advantage in presidential preference.
Among people who've voted previously, Obama and McCain are at 50-47 percent in this ABC News/Washington Post poll, not a statistically significant gap. But first-time voters favor Obama by a lopsided 73-26 percent, lifting him to an overall advantage.
There are striking vote-preference differences among other groups, many well-examined in the contest so far -- young voters vs. their elders, whites and blacks, "economy" voters vs. those more focused on other issues -- and others less so.
First-time voters are among the telling ones; they attest both to the Obama campaign's efforts to sign up new voters, and to the extraordinary level of enthusiasm among his supporters this year.
But there's a cautionary note for the Obama campaign: Turnout among first-time voters is challenging to predict, since they're clearly not in the habit.
That means targeted get-out-the-vote efforts can matter particularly with this group -- not just in how many vote, but in how those who do vote divide between the candidates.
Overall, two weeks before Election Day, Obama leads McCain by 53-44 percent among likely voters, unchanged from yesterday's tracking results. Obama's held the advantage since taking a clear lead on the strength of economic discontent in an ABC/Post poll on Sept. 22.
First-time voters account for 11 percent of all likely voters in this poll, matching their turnout in the 2004 presidential election.
According to the national exit poll that year, they voted 53-46 percent for Kerry vs. George W. Bush, a far narrower division than their vote preference today. (Bush won previous voters by 51-48 percent.)
Naturally, first-time likely voters are predominantly young, long Obama's best support group; 69 percent of them are under age 30. But young voters, in particular, can be skittish in terms of turnout.
First-time likely voters this year include three times as many Democrats as Republicans, a sharp shift from 2004, when partisanship was about even among first-timers. Given their youth, a third of likely first-time voters are liberals, vs. a quarter in 2004 (and more than among repeat voters this year, 20 percent).
Another difference among groups is based on where likely voters live: Obama leads by 30 points among city dwellers, but it's McCain by 23 points among rural Americans. Suburbanites divide almost exactly evenly.
Obama leads overall partly because of his slightly larger advantage among urban voters (64-34 percent, compared with McCain's 59-36 percent among rural voters), but also because there simply are more of them: Twenty-five percent of voters are urban, vs. 16 percent rural.
Divided suburbanites constitute the plurality, 46 percent of voters, splitting 48-47 percent between Obama and McCain.
Urban residents, as it happens, also are the most focused on the economy; 58 percent call it the single most important issue in their vote, compared with 46 percent of rural likely voters (suburban residents fall between the two). Partisanship fuels some of this; Democrats also are more focused on the economy, and they're more numerous in urban areas, Republicans in rural ones.
The economy overall continues to dominate; it's far and away the No. 1 issue to voters overall, cited by 52 percent. And as reported separately Tuesday, ABC/Post data show continued high levels of economic unease – with a dramatic effect on vote preferences.
Eighty-five percent of likely voters are worried about the economy's direction the next few years, 44 percent "very" worried; two-thirds are worried about their own family's finances, one in four very much so.
It matters: Among people who are "very" worried about the economy, Obama leads by 65-29 percent. Among everyone else – somewhat worried, or not too worried or not worried at all -- McCain leads, 54-43 percent.
With no high-level economic worry, in theory, there'd be no Obama lead.
The differences aren't quite so stark on personal finances; here Obama leads by a wide margin among the very worrieds (by 66-27 percent) and by 10 points among somewhat worrieds.
Those who aren't so worried split evenly; McCain leads only among those who aren't worried about their family finances at all. His problem is that they account for just 12 percent of likely voters.
Likely voters trust Obama over McCain to handle the economy, by 55-38 percent in the latest results. Obama also retains a narrower advantage on taxes, 50-43 percent, in four days of interviews completed Monday night -- an issue the two have contested especially sharply since Joe the Plumber entered the stage.
Obama's 17-point lead in trust to handle the economy is the largest for any candidate since Bill Clinton's in 1992 – the last time economic discontent approached its levels today.
On taxes, similarly, Obama's advantage this cycle is the first for a Democrat in ABC/Post pre-election polls since Clinton's in '92.
And as it happens, the weekly ABC News Consumer Comfort Index on Tuesday dropped to within a point of its record low in 22 years of weekly polls.
METHODOLOGY: Interviews for this ABC News/Washington Post tracking poll were conducted by telephone Oct. 17-20, 2008, among a random national sample of 1,324 likely voters, including landline and cell-phone-only respondents. Results on economic worry were conducted Oct. 16-19 among 1,336 likely voters. Results have a 2.5-point error margin for the full sample. Sampling, data collection and tabulation by TNS of Horsham, PA.