(J. Scott Applewhite/AP Photo)

Three months before the midterm elections a record number of Americans in the latest ABC News/Washington Post poll disapprove of their own representative in Congress - a potentially chilling signal for incumbents that marks the depths of the public's political discontent.

Insult, moreover, follows injury: Both political parties, for their part, are near their all-time lows in popularity.

See PDF with full results and charts here.

Just 41 percent in this national survey approve of the way their own representative in the U.S. House is handling his or her job, the lowest in ABC/Post polls dating back a quarter century, to May 1989. Fifty-one percent disapprove - more than half for the first time.

The result, extending a drop from last October, turns on its head the old chestnut that Americans hate Congress but love their Congress member. It also recalls an ABC/Post poll result in April, in which just 22 percent said they were inclined to re-elect their representative, a low also dating back to 1989. Were it not for gerrymandering, these are the kind of results that could portend a serious shakeup come Nov. 4.

The actual impact remains to be seen, given both the few competitive House districts and the low esteem in which both parties are held.

PARTY TIME - The grimmest score is the GOP's: A mere 35 percent express a favorable impression of the Republican Party, a number that's been lower just twice in polls since 1984 - 32 percent last October, just after the partial government shutdown in a Washington budget dispute; and 31 percent in December 1998, immediately after the impeachment of Bill Clinton.

The Democratic Party is seen favorably by more Americans, 49 percent in this poll, produced for ABC by Langer Research Associates. But that, similarly, is one of the party's lowest popularity ratings on record in 30 years.

The Democrats' 14-point advantage in favorability may look like an edge in the midterms, and indeed it may make them less vulnerable than they'd be otherwise. But other elements factor into election math, including turnout, which customarily favors the Republicans; the number of open Senate seats each party has to defend, higher this year for the Democrats; competitive House seats, which as noted are few; the quality of individual candidates; and the presence or absence of an overarching theme that can galvanize voters in one party's favor, which has yet to emerge.

What it does mean, undoubtedly, is that the public is in an extended political snit.

A confluence of factors likely is at play. One is the still-slow growth in jobs and wages that's marked the nation's tortuous emergence from the deepest and longest downturn since the Great Depression; another is the public's evident frustration with the political process (or lack thereof) in Washington.

Yet the partisanship that divides Washington is evident in public sentiment itself: Each side overwhelmingly likes its party and dislikes the other.

Specifically, 85 percent of Democrats see the Democratic Party favorably; exactly as many see the Republican Party unfavorably. An identical 85 percent of Republicans view the Democratic Party unfavorably, while 79 percent of Republicans express a favorable opinion of their own party.

The Democrats get a little boost out of their better in-party rating, and also benefit from the fact that there's more of them - 32 percent of Americans identify themselves as Democrats, vs. 22 percent who say they're Republicans, basically where it's been, on average, since 2009. The Democratic Party also gets a lift from independents; they frown on both parties, but more on the GOP (31-61 percent, favorable-unfavorable) than on the Democrats (a 41-50 percent split).

Independents, who tend to be less favorably inclined toward politics in general, are notably annoyed with their own representative: just 35 percent approve, while 56 percent disapprove. Approval rises to slightly fewer than half of Democrats and Republicans alike.

MORE GROUPS - Disapproval of "your own representative" peaks, at 58 percent, among Hispanics, perhaps expressing dissatisfaction with the stalled overhaul of immigration policy. Hispanics are particularly negative toward the Republican Party - 65 percent see it unfavorably, while 61 percent of Hispanics express a favorable opinion of the Democratic Party.

Blacks tilt even more heavily pro-Democratic (82 percent) and anti-Republican (81 percent). Indeed, whatever occurs in this year's midterms, the results among nonwhites overall underscore the GOP's challenges as whites' share of the nation's population shrinks. Seventy percent of nonwhites see the Republican Party unfavorably overall, while about as many, 68 percent, have a favorable opinion of the Democratic Party. Whites, for their part, are equally negative about both parties.

Among other groups, as long has been the case, the Democrats are more popular with women than with men. The gap between favorable ratings of the Democratic Party and the Republican Party among men is just 6 percentage points (44 vs. 38 percent). Among women it's 21 points (54 vs. 33 percent).

Combining race, sex and education shows a longstanding difference in one particular group: college-educated white women, who are much more favorably inclined toward the Democratic than the Republican Party. White women who lack a college degree see both parties equally, and white men are more favorable toward the GOP, regardless of education.

Single women also are a markedly more Democratic-inclined group. But married men tilt heavily in the opposite direction - toward the GOP - and there's twice as many of them. Of such threads are election strategies woven.

In addition to differences in party favorability, there's also a striking gap between single women and married men in their disapproval of their representative in Congress (a 21-point gap) and a similar gap between college-educated white women vs. non-college-educated white men, 22 points. In both cases, men are more critical of their representative than are women.

Age is another partisan factor, with a wide 26-point gap in favorability for the Democrats vs. the Republicans among young adults, age 18 to 29. That said, they're a weak turnout group, especially in midterms. And conservatives - more apt to vote when they're fired up - are more likely to favor the GOP than the Democratic Party by a 31-point margin.

METHODOLOGY - This ABC News/Washington Post poll was conducted by landline and cell phone July 30-Aug. 3, 2014, in English and Spanish, among a random national sample of 1,029 adults. Results have a margin of sampling error of 3.5 points. Partisan divisions are 32-22-41 percent, Democrats-Republicans-independents. The survey was produced for ABC News by Langer Research Associates of New York, N.Y.