THERE WAS A HINT of history repeating itself last week when the Bangor Daily News endorsed Herman C. "Buddy" Frankland, 43, a Baptist minister running as an independent candidate for governor, and then reported poll findings showing him gaining support. Four years ago, a similar sequence presaged the upset victory of independent Gov. James B. Longley. But Longley, retiring voluntarily this year at the height of his popularity, declined Friday to endorse a successor, and Atty. Gen. Joseph E. Brennan (D), 44, remains the favorite in the race. The Daily News poll showed him leading state House minority leader Linwood E. Palmer Jr. (R), 56, by 17 points, with Frankland third.

Sen. William D. Hathaway (D), 54, an outspoken liberal, continued to battle uphill against his progressive GOP challenger, Rep. WIlliam S. Cohen (R), 38. Hathaway, as understated in his approach to voters as Cohen is aggressive, may have been helped by his central role in a last-minute settlement of the Indian claims question that has dominated state politics, and by campaign appearances by President Carter and Sen. Edward M. Kennedy (D-Mass.). He also gets the benefit of Brennan's strong campaign organization. But broadcast and published polls this week give Cohen a 12-to 20-point lead, and he is favored.

State Sen. Olympia J. Snowe (R) is favored to defeat secretary of state Markham L. Gartley (D) for Cohen's House seat.