Instructions: In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.
Input: Passage: On January 16, 1979, Clements succeeded Democrat Dolph Briscoe as governor of Texas. To win the position, he first defeated State Representative Ray Hutchison in the Republican primary by a lopsided vote of 115,345 to 38,268. Hutchison, a prominent Dallas attorney, is the second husband of Texas State Treasurer (1991–1993) and U.S. Senator Kay Bailey Hutchison, who served from 1993 to 2013. Clements enjoyed the support of former state party chairman Peter O'Donnell, organizer of the Draft Goldwater Committee in 1963-1964. O'Donnell became a key adviser to Clements, who won the general election held on November 8, 1978, by having narrowly defeated Democratic former Texas Supreme Court Chief Justice John Luke Hill, who had also served six years as state attorney general. Clements polled 1,183,828 votes (49.96 percent) to Hill's 1,166,919 votes (49.24 percent). The La Raza nominee, Mario C. Compean, and two other minor candidates split the remaining 18,942 votes. The more liberal Hill, who had also once been the appointed Secretary of State of Texas, had defeated Briscoe in the primary.
 Link Information: 

Dolph Briscoe Jr. (April 23, 1923 – June 27, 2010) was an American rancher and businessman who was the 41st Governor of Texas between 1973 and 1979 Question: How long had Dolph Briscoe been serving as governor of Texas for when Clements replaced him?
Output:
Answer: 6