Tampa, Florida (CNN) - A top policy adviser to former Minnesota Gov. Tim Pawlenty's has left the Republican's presidential campaign.
Al Hubbard, a former director of the National Economic Council under George W. Bush, had been the chairman of Pawlenty's "policy efforts" but is no longer with the campaign, a Republican source told CNN.
Pawlenty spokesman Alex Conant confirmed the departure.
"Mr. Hubbard is a financial contributor, became busy with work and is not operating in the policy role, but we're grateful he gave us the maximum contribution," Conant said in an email.
Hubbard, a co-founder of an Indianapolis investment firm, is a political confidante to Indiana Gov. Mitch Daniels and played an instrumental role in mapping out a potential Daniels presidential campaign earlier this year.
Daniels ultimately decided against a run, and Hubbard signed on with Pawlenty in June.
"Al Hubbard not only has clout with the vast network of Gov. Daniels' supporters, but also carries weight with policy makers and thought leaders nationally," Pawlenty said in a statement at the time. "His addition to our team adds even more momentum to my campaign that is focused on offering honest solutions to the challenges facing America."
Hubbard did not respond to calls or emails seeking comment.