Story highlights Bill Clinton gave his final speech at the Clinton Global Initiative on Wednesday

Republicans have tried to turn the Clinton Foundation into a blemish against Hillary Clinton

(CNN) Bill Clinton used his final speech at the Clinton Global Initiative on Wednesday to tout the charity work it does around the globe, implicitly countering Republicans' accusation that the organization provided a way for wealthy donors to buy access to Hillary Clinton.

stressed what CGI -- which is part of the foundation and matches funders with causes -- has accomplished over the last 15 years. Bill Clinton, in what aides said was a speech he wrote himself,stressed what CGI -- which is part of the foundation and matches funders with causes -- has accomplished over the last 15 years. He said in August that this month's CGI meeting would be his last, and he plans to step down from the foundation's board of directors if Hillary Clinton wins in November.

"People may tell you you're making incremental change. But look back after 11 years and see what the aggregate is," the former president said. "None of this could have happened without the belief that progress is possible."

Advisers said Clinton hoped that the speech will provide a strong rebuttal to what he sees as partisan attacks on his foundation. He did not explicitly bring up how it had been injected into the 2016 campaign, but the 42nd president did hint at the criticisms.

"This is a time when this sort of talk is not in fashion all over the world," Clinton said. "It's kind of a crazy time."

Read More