Republican presidential candidate and former Massachusetts Gov. Mitt Romney greets supporters as he campaigns at the Pensacola Civic Center in Pensacola, Fla., Saturday, Oct. 27, 2012. / Charles Dharapak/AP Photo

Mitt Romney has matched Barack Obama on the question of who's presented a clearer economic plan, a measure on which the president held a broad 16-point advantage this summer - further evidence of the underlying shifts that make the 2012 presidential race so close.

Likely voters in the latest ABC News/Washington Post poll divide by 43-43 percent on who's offered a clearer plan for the economy, compared with a 49-33 percent division in Obama's favor on the same question in July - improvement for Romney as the campaign's progressed.

See PDF with full results and charts here.

Romney's also advanced in another area, affirmative voting, measured by the share of his backers who say they mainly support him rather than oppose Obama. Yet Romney still trails Obama on this potentially motivational measure, one reason the president is still so competitive.

The race remains very narrowly divided - 49 percent support for Romney, 48 percent for Obama among likely voters in this poll, produced for ABC by Langer Research Associates. That almost precisely matches the average, 48-48 percent, in 11 ABC/Post polls since midsummer. Even with gains by Romney on some fundamentals, there's been no breakout in this remarkably close contest. Notably, neither candidate has yet received majority support.

FOR/AGAINST - Among Obama's supporters, 77 percent say they're mainly for him, rather than chiefly against Romney. The affirmative vote for Romney is lower - 58 percent. But that's up by 10 percentage points since just after the conventions, and by a broad 22 points since July.

Comparisons to the last incumbent election, in 2004, are instructive: Eighty-six percent of George W. Bush's supporters were mainly "for" him rather than "against" John Kerry, while only 39 percent of Kerry's support was affirmative. Obama's affirmative support lags Bush's by 9 points, and Romney's exceeds Kerry's by 19; as a result, Obama's 19-point lead in affirmative voting pales compared with Bush's 47-point advantage in this measure eight years ago.

The question is whether negative voting is sufficient to motivate turnout - particularly among the more than third of Romney's supporters who are mainly against Obama, not for Romney. (In another measure, the candidates are still essentially even in "strong" enthusiasm among their supporters, also better for Romney than it was before the debates.)

MOMENTUM - As first noted Friday, Obama's managed to stem Romney's recent advances on some fundamental measures, raising questions about what had been clear post-debate momentum for the Republican.

Romney had moved by midweek to his first significant advantage in trust to handle the economy, (a 9-point lead) and battled Obama to virtual parity on economic empathy - who best understands Americans' economic problems. Today Romney still leads on the economy, by 7 points - no real slippage, but no further progress. On empathy, it's a non-significant Obama +3, again no real change from midweek, but tighter than Obama's +9 in mid-October.

VOTED? - Early turnout, so far, favors Obama: Eleven percent of likely voters in this survey say in fact that they've already voted, and they report having favored Obama by 57-40 percent, almost exactly his margin among early voters in ABC/Post polling in 2008.

Romney still has time to catch up; perhaps more important, he leads by 11 points among likely voters who plan to cast their ballots on Election Day. At this point in 2008, by contrast, Obama and John McCain were essentially even among Election Day likely voters, 49-47 percent.

While early voters so far are favoring Obama, Romney, as noted in Friday's analysis, is keeping pace with him on another measure of the ground game, voter contact. Equal numbers of likely voters say they've been contacted by the Obama and Romney campaigns (23 percent in both cases), an effort in which Obama surpassed McCain in 2008.

Obama and Romney also remain very close in contact efficiency - reaching likely voters who are their actual supporters - another area in which Obama trumped McCain.

Homing in on the 10 states designated as battlegrounds by the ABC News Political Unit (see the methodology section below for the list), contact again is very evenly matched - 43 percent say they've heard from Obama's campaign, 41 percent from Romney's. Obama had led by 13 points in battleground-state contacts two weeks ago.

Vote preferences in those battleground states also are extremely close - 48-50 percent, Obama-Romney. That compares with a 16-point Obama lead in the strongly Democratic states, and a 19-point advantage for Romney in those designated as strongly Republican.

GROUPS - Finally, the election remains marked by broad differences across partisan and demographic groups. The gender gap, for example, remains wide, an 11-point lead for Obama among women vs. a 13-point lead for Romney among men.

Romney has a 58-39 percent lead among whites, pushed ahead by 63 percent support among white men (vs. 54 percent among white women); McCain's support from white men in 2008, for comparison, was 57 percent. Also Romney is winning support from 81 percent of evangelical white Protestants, surpassing McCain's 73 percent from this group in the 2008 exit poll.

Obama counters with backing from nearly eight in 10 nonwhites, who've made up a growing share of the electorate in the past generation; they account for one in four likely voters in this survey. And Obama's winning support from 64 percent of 18- to -29-year olds, virtually on pace with his 2008 record in this group. The essential question in a close race of course, is who among these sharply divided groups proves motivated enough to cast their ballots.

METHODOLOGY - This ABC News/Washington Post poll was conducted by telephone Oct. 23-26, 2012, among a random national sample of 1,295 likely voters, including landline and cell-phone-only respondents. Results have a margin of sampling error of 3.5 points, including design effect. (Questions 5a, 5b and 13d were asked Oct. 24-26 among 962 likely voters; those results have a 4-point error margin.) The survey was produced for ABC News by Langer Research Associates of New York, N.Y., with sampling, data collection and tabulation by Abt-SRBI of New York, N.Y.

Partisan divisions in this survey, Democrats-Republicans-independents, are 35-29-33 percent among likely voters. Partisan divisions in the 2008 exit poll were 39-32-29 percent. "Battleground states" as designated by the ABC News Political Unit are Colorado, Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio, Pennsylvania, Virginia and Wisconsin.