Sen. Edward M. Kennedy of Massachusetts continues to run far ahead of the field of 1980 Democratic presidential possibilities and outdistances President Carter by more than a 2-to-1 ratio.

Asked to choose among nine candidates, 53 percent of the Democrats surveyed named Kennedy, while, 21 percent picked Carter and 8 percent Gov. Edmund G (Jerry) Brown Jr. of California.

If Kennedy's name is excluded, however, Brown trails Carter by only 34 to 19 percent. Next (with Kennedy out) are Vice President Mondale with 12 percent and Sen. George McGovern of South Dakota with 11 percent.

Only twice before in the 47-year history of the Gallup Poll has a potential presidential nominee led an incumbent in these tests of nomination strength-and never to the extent that Kennedy now leads Carter.

In 1967 Sen. Robert F. Kennedy (D.N.Y) led President Johnson 43 to 34 percent among Democrats tested, and in 1975 Republican Ronald Reagan led President Ford 40 to 32 percent.

Here are the questions asked:

Here is a list of people who have been mentioned as possible presidential candidates for the Democratic Party in 1980. Which ONE would you like to see nominated as the Democratic candidate for president in 1980? And who would be your Second choice ? (TABLE) (COLUMN)First Choice(COLUMN)With Kennedy Out Kennedy(COLUMN)53%(COLUMN) Carter(COLUMN)21(COLUMN)34 Brown(COLUMN)8(COLUMN)19 Mondale(COLUMN)5(COLUMN)12 McGovern(COLUMN)4(COLUMN)11 Jackson(COLUMN)3(COLUMN)6 Moynihan(COLUMN)2(COLUMN)4 Church(COLUMN)2(COLUMN)6 $ udall (COLUMN)2 Undecided(COLUMN)2(COLUMN)6(END TABLE) * Less than 1 percent

When all Democratic voters in the current survey were asked to choose between Kennedy and Carter, Kennedy won 66 to 30 percent. In a similar contest between Carter and Brown, the president won 54 to 37 percent.

The following tables show the trends in these showdown tests:



As both trends show, the Carter vote vis-a-vis each potential rival has remained stable despite a steady down-trend in approval ratings for Carter's handling of the presidency.

The results reported today are based on in-person interviews with 502 Democrats out of 1,272 adults interviewed in more than 300 scientifically-selected localities across the nation during the period July 13-15.