The correct answer to this open question is the following.
Unfortunately, you forgot to mention what kind of document you are talking about. Yo did not attach anything.
We assume that you are referring to the famous document he created titled "Contract With America." If that is the case, then we can say the following,
House Speaker Newt Gingrich felt emboldened enough to offer a document like his contract with America in 1994 because he knew that was the exact time to make a "revival" for the Republican values and get the trust of teh American people with the ten points of his contract.
Let's remember that Bill Clinton a Democrat, was the President of the United States.
Newt Gingrich proposed attractive actions such as tax reductions, a better budget, and a reformation to improve the wealth of the American people. More than 300 Republicans that were candidates before the midterm elections signed the document, providing strong support.
The result?
The Republicans won 12 governorships and took control of the Senate and the House of Representatives.