Conversation so far:
What is known of bruce willis' political views?
In 1988, Bruce Willis and then-wife Demi Moore campaigned for Democratic Massachusetts Governor Michael Dukakis's Presidential bid.
What more is known of Governor Michael Dukakis's campaign for President?
Using the phenomenon termed the Massachusetts Miracle to promote his campaign, Michael Dukakis sought the Democratic Party nomination for President of the United States in 1988.
What followed Bruce Willis' involvement in Governor Dukakis's presidential campaign?
Four years later, Bruce Willis supported President George H. W. Bush for reelection.
Did Bruce Willis play any prominent role in politics?
In 1996, Bruce Willis declined to endorse Clinton's Republican opponent Bob Dole.

Question: Why did he decline?
Self-contained rewrite: Why did Bruce Willis decline to endorse the politician Bob Dole?