WASHINGTON (AP) _ Jesse Jackson won 96 percent of the black vote and 10 percent of the white vote in Super Tuesday's Democratic primaries, winning greater support from both races than in his 1984 quest for the presidency, according to ABC News exit polls.

Four years ago, Walter Mondale eroded Jackson's strength among black voters, and fewer whites were willing to cast their ballot for the black minister and longtime civil rights activist.

Jackson complained bitterly in 1984 about party rules he said were stacked against him and diluted his delegate strength.

But the rules changed for 1988, and Jackson demonstrated in New England and the Midwest - and again in his native South on Tuesday - that he has broadened his base.

Voters polled by ABC after casting ballots Tuesday gave Jackson high marks for his ability to handle foreign affairs, protect the poor and elderly and hold down unemployment.

Among those who voted in Democratic primaries, 29 percent said they definitely would not vote for Jackson for president; 45 percent nixed Republican Pat Robertson; 37 percent ruled out George Bush and 36 percent said no to Democrat Gary Hart.

In the Democratic primaries in 1984, Jackson got 1 percent of the white vote in Alabama and 55 percent of the black vote. On Tuesday, according to ABC's exit polls, Jackson got 6 percent of the white Alabama vote and 96 percent of the black vote.

To illustrate Jackson's black strength, take a closer look at Alabama. At a virtually all-black precinct in Mobile County, Ala., Jackson got 1,837 votes to second-place Albert Gore Jr.'s 31. In Macon County, which is about 90 percent black, Jackson led with 2,540 to second-place Gore's 43.

Likewise, in Florida, where Jackson pulled in just 1 percent of the white vote and 58 percent of the black vote in 1984, Jackson was pulling in 7 percent of the white vote and 82 percent of the black vote Tuesday.

The ABC exit polls had a five point margin of error in either direction.

Blacks comprise almost one-fourth of the Democratic vote across the South, and they make up nearly half the electorate in such Deep South states as Alabama and Mississippi.

No one doubted Jackson's ability to snare upwards of 80 percent of the black vote in the 20 Super Tuesday states.

The question was whether he could run anywhere near as strongly among Southern white voters as he has in such largely white states as Iowa, Maine and Minnesota.

An ABC News poll of 8,659 potential voters in Super Tuesday primary states, completed Sunday, indicated that Jackson was leading in seven states - Alabama, Mississippi, Arkansas, Georgia, Louisiana, North Carolina and Virginia - and running second or tied for second in Florida, Texas, Maryland and Tennessee.

Looking just at the dozen Southern states with primaries, ABC said its advance poll indicated ''Jackson is getting 78 percent of the black vote and only seven percent of the white vote.'' It said that ''represents no appreciable increase from the white vote percentage Jackson achieved in the 1984 perimaries.''

But Frank Dexter Brown, associate director of communications for the Joint Center for Political Studies, a black-oriented think tank based in Washington, said Jackson has defied expectations with his showings this year in Maine, New Hampshire, Vermont, Minnesota and Iowa.

Jackson got 28 percent of the vote in Maine compared to 1 percent four years earlier. He also got 28 percent in Vermont, 20 percent in a second-place finish in Minnesota, 11 percent in the Iowa caucuses and 8 percent in New Hampshire.

Most national polls have given Jackson 4 percent to 5 percent of the white vote.

A survey last August by the Joint Center for Political Studies found 80 percent of blacks and 10 percent of whites supported Jackson.

In the 1984 primaries, Jackson pulled in 18 percent of the vote nationally but wound up with just 12 percent of the delegates. Blacks comprise about 12 percent of the U.S. population and, according to the Joint Center, about 11 percent of those of voting age.

Delegates are awarded by congressional district, not statewide, so it is still possible for a candidate to wind up with a smaller share of delegates in some states than his popular vote.

But Jackson stood to profit from the lower threshold of votes needed in each congressional district to gain delegates. It was 20 percent in 1984; now it is 15 percent.

In 1984, Jackson wound up with seven of Kentucky's 63 delegates - 11 percent - despite pulling in 18 percent of the statewide vote.

His campaign manager, Gerald Austin, has said Jackson's strategy this year is to pull in up to 10 percent of the white vote as well as his solid base of black support.

More than 900 of the 1,307 delegates at stake Tuesday were in Southern states, and Austin predicted Jackson could win 250 to 350 of them.