His father was William A. Ashbrook, a newspaper editor, businessman, and Congressman.

After graduating from Harvard University in 1952 and from Ohio State University's law school in 1955, Ashbrook became publisher of his late father's newspaper, the Johnstown Independent. He was elected to the Ohio House of Representatives in 1956 and served two terms. In 1960 his father's old seat in the U.S. House of Representatives opened up, and Ashbrook ran for and won it.

In the 1972 presidential election, Ashbrook ran against incumbent Richard Nixon in some state primaries as an alternative conservative candidate. His slogan "No Left Turns" was illustrated by a mock traffic symbol of a left-turn arrow with a superimposed No symbol. It was meant to symbolize the frustration of some conservatives with Nixon, whom they saw as having abandoned conservative principles and "turned left" on issues such as budget deficits, affirmative action, the creation of the Environmental Protection Agency, wage and price controls, the gold standard, and most of all, improving relations with the Soviet Union and the People's Republic of China with his policy of détente.

He competed in the New Hampshire (9.8f the vote), Florida (9� and California (10�primaries. He withdrew from the race after the California primary and "with great relectance" Nixon. To this day, his campaign, although of minimal immediate impact, is remembered fondly by conservatives who admire Ashbrook for having stood for their principles.

When Nixon became mired in the Watergate scandal, Ashbrook became the first House Republican to call for the President's resignation.

In 1982, after announcing his intention to seek the Republican nomination to challenge incumbent Democratic U.S. Senator Howard Metzenbaum, Ashbrook died.

His wife, Jean Spencer Ashbrook, was chosen in a special election to serve the remainder of his Congressional term.

The Ashbrook Center for Public Affairs at Ashland University is named for Ashbrook.