Former Governor Jeb Bush (R-FL) addresses the National Review Institute's 2015 Ideas Summit in Washington on April 30. (REUTERS/Jonathan Ernst)

LANSING, Mich. -- If a former two-term governor wanted to remind voters that he led the response to eight hurricanes, four tropical storms and an anthrax outbreak, where might he visit?

For Jeb Bush, it was a factory that makes an anthrax vaccine.

The former Florida governor kicked off a two-day visit to Michigan on Thursday by visiting Emergent Biosolutions, which produces an anthrax vaccine stockpiled by the U.S. government and administered to military personnel to protect against bioterrorism.

The venue lent itself well to a modified sales pitch Bush is delivering to voters: That he's a serious, tested leader in a rapidly expanding field of less experienced Republican presidential contenders.

It also came as anthrax was thrust back into the news: The Pentagon disclosed Wednesday that an Army laboratory in Utah inadvertently distributed live samples of anthrax to facilities in nine states.

Speaking to about 200 company employees here, Bush reminded the crowd that he dealt with the first anthrax attack after the Sept. 11, 2001 terrorist attacks. With the country still reeling, a new threat emerged in October 2001 when a photo editor at the Boca Raton, Fla., offices of the National Enquirer was exposed to anthrax and died soon after.

"You all understand what anthrax is, but trust me, shortly after 9/11 I had no clue," Bush told the workers.

"I learned a lot about this, and in the post-9/11 environment, one of the responsibilities of governors that take their jobs seriously is to try to anticipate what the next attack might look like, or how do you respond to biological attack or any kind of attack," he added. "And so we did a lot of training in this regard and we developed a defense of the homeland across the spectrum because of what happened right after 9/11."

Bush said the lesson learned during the outbreak his administration prepare for eight hurricanes and four tropical storms that later hit over a 17-month time period.

"We're in the tenth anniversary of Katrina and Florida, I'm really proud of the public servants that served the state when people really needed it," he said.

Bush's former head of emergency management, W. Craig Fugate, now serves as head of the Federal Emergency Management Agency. When President Obama tapped Fugate for the post, he credited him and Bush for their stewardship of the state during those storms. In a 2010 Washington Post profile of Fugate, Bush said that "the administration is fortunate to have him on their team."

Bush first road-tested his new serious-and-experienced sales pitch during a conference call with Alabama Republicans on Wednesday night. He suggested that others already in the race were being needlessly combative and that the eventual GOP presidential nominee should be "hopeful and optimistic instead of grumpy and kind of reactionary."

[Read more: Jeb Bush sharpens critique of would-be opponents]

"I think a lot of leaders in public life or aspiring leaders get overwhelmed by the here and now, they change their views because they’re trying to mirror the sentiments of the time. And they get lost," he said.

Bush arrived in Michigan Wednesday for two days of private meetings and public events. He's scheduled to address a Lincoln Day dinner Thursday night. He'll travel to Nashville to appear at a similar dinner on Saturday night and appear next Tuesday at an economic forum in Orlando, hosted by Florida Republican Gov. Rick Scott.