Legislature

On June 15, 1960, he filed to run for the Democratic nomination for one of Lincoln County's three seats in the Wyoming House of Representatives and won in the general election.^[6] Upon taking office he introduced a bill that would repeal Wyoming's inheritance tax.^[7] However, after the initial forty day session of the house he resigned on March 10, 1961, to become Lincoln County's attorney again, but filed to run for the house again in 1962 and won a seat in the general election placing second.^[8][9] In the 1964 elections the Democrats took control of the state house and in the 1965 legislative session Herschler was selected as House Majority Whip and made chairman of the House Judiciary Committee.^[10][11] In 1967, he cosponsored the first air pollution control bill in Wyoming and on September 13, 1968, he was elected as president of the Wyoming State Bar Association.^[12]

He was considered a possible candidate for governor in the 1970 election, but stated on December 10, 1969, that he was not interested in running for governor.^[13] On April 27, 1970, he announced that he would run for the Democratic nomination for Wyoming's at-large congressional district, but was defeated by former Representative Teno Roncalio who went on to win in the general election. On October 27, he endorsed Roncalio following his defeat in the August primary.^[14][15] In 1971 he stated that he was contacted by Governor Stanley K. Hathaway as being a possible appointment to the Wyoming Supreme Court, but was not selected.^[16]

Governor

On May 23, 1974, he announced that he would seek the Democratic nomination for governor and defeated former state senator Dick Jones in the general election.^[17] He was critical of President Jimmy Carter for his agricultural stances and water projects and when Carter visited Grand Teton National Park from August 24 to September 1, 1978, he had Herschler notified that he was not invited.^[18]

In 1978, he narrowly won reelection by 2,377 votes, but easily won reelection to a third term in 1982 becoming Wyoming's only governor to serve more than two terms. In 1986 he announced that he would not seek reelection to a fourth term.

In September 1981 Cody, Wyoming hosted the Western Governors Association's annual conference of that year and Herschler was selected as president of the Western Conference to serve a one-year term from 1981 to 1982.^[19][20]

In 1985, he commuted the sentences and ordered the releases of Deborah and Richard Janhke Jr., who were both convicted in 1983 of manslaughter in the 1982 death of their abusive father, Richard Jahnke Sr., in Cheyenne and who were the subjects of the television film Right to Kill? In September 1985 he had to file for bankruptcy due to the failure of his 18,500 acre Yellowstone Ranch with almost $6 million in debt.^[21]

During his tenure he vetoed more bills than any other governor in Wyoming's history, but none of his vetoes were ever overridden despite the Republicans holding supermajorities in both chambers during most of his tenure.^[22] Some of his vetoes were unpopular such as when in 1984 he vetoed a homeowners tax credit program stating that it would subsidize homeowners who did not need it which resulted in the Democrats losing seven seats in the House of Representatives.