Who said the following about growing the economy?

Who said:

 “In short, to increase demand and lift the economy, the Federal Government's most useful role is not to rush into a program of excessive increases in public expenditures, but to expand the incentives and opportunities for private expenditures.”

Ronald Reagan?  George Bush?  Mitt Romney?  Newt Gingrich? 

 See the answer below.

President John Kennedy, December 14, 1962