Two voting blocs and their impact on Keystone State primary

''We won Philadelphia!'' Jesse Jackson raised thumbs up for victory here - where he was the top vote-getter with 39 percent - even though he ran a distant third in Tuesday's Pennsylvania primary.

Statewide, Mr. Jackson pulled 17 percent of the vote, 4 points above what preelection polls predicted. He trailed front-runner Walter Mondale, with 47 percent, and Gary Hart, with 35 percent.

Once more Jackson did not reach the 5 percent of the state's white vote that analysts say would signal a noticeable following among whites. This leaves his hoped-for ''rainbow coalition'' still stalled.

A lingering problem is the controversy over Jackson's references to Jews, and subsequent threats by the Nation of Islam leader, Louis Farrakhan, against a Washington Post reporter who made public Jackson's remarks. Reporters ask Jackson about a possible white voter backlash, but he dismisses this talk as ''rumor.''

Nevertheless, the Jackson vote in Pennsylvania recertified him as a candidate who will carry considerable influence to the Democratic National Convention in San Francisco in July. His weapons will be:

A strong black following. Jackson won 80 percent of the state's black vote. He drew only 77 percent of Philadelphia's black ballots, probably because the city's black mayor, W. Wilson Goode, endorsed Mr. Mondale. This was a good showing in a primary in which two Goode-backed candidates for the state Senate won upset victories over incumbents.

A critical block of delegates. If the national convention should reach a stalemate, Jackson's cluster could be decisive in selection of the party's nominee. It is estimated by political observers that the ''country preacher'' could bring 200 or more delegates to the convention.

Clout in determining the party's platform. Jackson's key role is likely to be that of spokesman for voting rights of black people. A critical issue would be the runoff votes in Southern states that call for a second ballot if no candidate wins a majority vote in the party primary. Jackson wants the runoff eliminated, claiming it hurts black candidates and defies the one-man, one-vote policy of the Voting Rights Act.

Jackson's campaign leaders will work on two activities designed to increase white support of his candidacy - a planned ''rainbow convention'' to set forth the black agenda for the Democratic National Convention in July and a trip to troubled Nicaragua and other troubled Latin American nations.

''We haven't yet set a date for our rainbow convention,'' Jackson said in a short interview Tuesday night. ''But our goal will be to develop a program that will meet the needs of blacks, minorities, women, and the unemployed.''

But while black turnout in Philadelphia was reported to be slightly higher than in past primaries, white turnout was lower. One analysis of the Philadelphia vote noted that Jackson received only 8 percent of the Jewish vote on Tuesday, compared with the city's mayoral primary last year in which Mr. Goode won 50 percent of the Jewish vote.

No Nation of Islam representatives (also known as Black Muslims) stood with Jackson at any of his weekend rallies, but Mr. Farrakhan spoke at a Youth for Jackson-sponsored election-eve rally that drew more than 2,000 people and raised for its support at his postelection gathering.

''I still expect to get more white support,'' Jackson said. ''We have been separated so long that it takes time for us to get together. Things will improve before (the Democratic National Convention in) San Francisco.''

A planning session for Jackson's ''rainbow convention'' has been held in New York City, a campaign aide says. He says the proposed meeting will likely be held in late June somewhere in California after that state's June 5 primary. Resolutions from that gathering will be promoted at the Democratic National Convention.

''If I were president, I would stop the planting of mines in the harbors of Nicaragua,'' Jackson said. ''Our plans are to visit Nicaragua some time between May 8 and May 15,'' shortly after the May 5 Texas caucuses.

Jackson has received invitations to ''several countries,'' says Preston Love, a key aide. ''He (Jackson) wants this to be more than a quick-look visit.'' Other countries that may be visited include Mexico, Panama, and Honduras, he adds.

Jackson swung through Philadelphia on election day, addressing churchgoers at a sunrise service, students at Temple University and LaSalle College, and a noon street rally at the ''Clothespin'' (a modern sculpture) downtown.

His message: ''Vote for peace. Vote for social justice. Vote for the 'rainbow.' Vote for an urban policy.

''We can reduce the defense budget by $20 billion and use this money to provide aid to education, build 250,000 bridges, put the steelworkers back to work, create new jobs. . . . We have three candidates and two directions. The other two (candidates) offer liberalism; I offer liberation. There comes a time when you must act. Others advocate. I act. Get a new direction. Vote for me.''