The preliminary count of votes cast in Tuesday's Cambridge City Council election indicate certain election for incumbent Independent Walter J. Sullivan and a likely majority on the council for the Independent slate.

The election commission began the week-long task of sorting and resorting ballots yesterday by grouping the ballots by first choices in order to establish the number of votes necessary for a candidate to win, the first procedure in a proportional representation (P.R.) election.

The quota was set at 2573 votes. A total of 26,217 votes were cast, 491 of which were found to be invalid.

Voter turnout was down 12 per cent from two years ago despite the fact that voter registration has increased by almost 10 per cent during the same period.

The only clear winner at this point is Sullivan who, with 3460 first-choice votes, is clearly above quota. No results will be official until tomorrow when the count begins over again and votes are redistributed according to the rules of P.R.

However, election commissioner Edward J. Samp Jr. said yesterday that the preliminary count is generally "very indicative" of the final results.

Saundra Graham, a candidate on the Grass Roots Organization (GRO) slate, received the second highest total, followed by fellow incumbents Thomas W. Danehy, an Independent, and Barbara N. Ackermann, a CCA-endorsed candidate.

Leonard J. Russell, who has placed tenth in the past two races for city council, finished fifth in yesterday's count and it appears likely that the Independent will be among the nine councillors sworn into office next January.

Russell was followed in first-choice votes by Independent incumbent Alfred E. Vellucci, CCA newcomer David Wylie, CCA incumbent Francis H. Duehay '55, and Independent newcomer Donald A. Fantini.

This initial ordering could change substantially with the addition of redistributed votes, especially Sullivan's 800 excess votes.

Therefore, even though they did not place among yesterday's top nine, Independents Edward J. Stewart, Daniel J. Clinton and Henry F. Owens III and CCA newcomer Dominic H. Christofaro Jr. could theoretically win one or more of the bottom seats on the council.

John Brode '52, a GRO candidate, and Jon Halberstadt, a CCA candidate, each garnered only 261 votes despite very active and visible campaigns.

The scene at the Longfellow gymnasium yesterday, where the counting is taking place, was relaxed and informal. The clerks, who appeared to be mostly housewives and senior citizens, conducted their work in coffee-klatch fashion--a marked contrast to the high tension, computerized systems used in most elections.

The clerks, who are recruited every two years for the job of counting and sorting, are paid for the session's work.

During the day, several teachers brought their students to the scene for an on-the-spot civics class. Later on in the afternoon, friends and neighbors of candidates and clerks dropped by to chat and check results