IF YOU'RE getting tired of the political news from Chicago, take a look at what's happening in Philadelphia. The nation's fourth largest city is also having a seriously contested race for mayor this year, featuring a contest between a black and a white in the Democratic primary next Tuesday. But so far the campaign has been conducted in a manner that does a reasonably good job of living up to the literal meaning of the city's name--brotherly love.

For this, credit must go to the two leading contenders for the office. Wilson Goode, as former managing director of the city government under outgoing Mayor William Green, is campaigning as an experienced and competent administrator. He has avoided the kind of racial appeals to black voters that some other black politicians in Philadelphia and elsewhere have indulged in. Former Mayor Frank Rizzo, trying for a comeback, has avoided the incendiary rhetoric for which he was famous in the 1971 and 1975 campaigns. He did much to lower the tone of Philadelphia's public life in the 1970s, and now he is doing his part to elevate it.

It is true that the electorate in Philadelphia is divided largely on racial lines. The overwhelming majority of blacks is expected to vote for Mr. Goode and a large majority of whites for Mr. Rizzo. But it's also fair to say that most voters will base their decisions on their estimates of the candidates' abilities and their positions on issues relating to city government.

No one can be sure whether Mr. Goode, the favorite, will win the primary, or whether the Democratic nominee will win the general election, since the Republicans have three reputable candidates: former congressman Charles Dougherty, former city controller Tom Gola, and stockbroker John Egan. But regardless of the result, the election plainly has not stimulated the fears or aroused the hatred apparent in Chicago.

Some observers saw in the Chicago mayor's race a harbinger of future urban conflicts. We're inclined to think the example being set by Philadelphia is the wave of the future. It gets less attention because, in politics, good news tends to be no news. So forget the Philadelphia jokes, and give Philadelphia's politicians and voters credit for a campaign well done.