Former Florida Gov. Jeb Bush announced Tuesday that he plans to "actively explore" a run for president, taking his most definitive step yet toward mounting a 2016 campaign. 

The former GOP governor -- and son and brother of past Republican presidents -- also said he plans to launch a new political operation allowing him to raise money for like-minded politicians. 

In a message posted on social media on Tuesday, Bush said he's discussed his plans with his family. 

"As a result of these conversations and thoughtful consideration of the kind of strong leadership I think America needs, I have decided to actively explore the possibility of running for President of the United States," Bush said. 

He added, "In the coming months, I hope to visit with many of you and have a conversation about restoring the promise of America." 

Kristy Campbell, a spokeswoman for Bush, said he has not yet made a final decision on whether to seek the Republican Party's presidential nomination in 2016. She said Tuesday's announcement marks the "next phase" of his consideration process. 

The latest headlines on the 2016 elections from the biggest name in politics. See Latest Coverage →

She said he will now gauge "if there is support for a potential candidacy." 

That phase will include an expansion of Bush's political operations. He said Tuesday he will start his own leadership political action committee in January, which will allow him to raise money and use it to support candidates in other races. 

The Democratic National Committee, in response, brushed off the announcement. 

"Isn't this what he's been doing all along?" DNC Communications Director Mo Elleithee said in a statement. "I don't know what the difference is between 'thinking about' running and 'actively exploring' running, but I suspect it has a lot to do with keeping his name in the news. However you see it, there's no parsing this simple fact: Jeb Bush has fully embraced the failed economic agenda that benefits only a select few at the expense of the middle class. That's not going to change no matter how many different ways he says he may run." 

In his statement, Bush said his new political committee "will help me facilitate conversations with citizens across America to discuss the most critical challenges facing our exceptional nation. The PAC's purpose will be to support leaders, ideas and policies that will expand opportunity and prosperity for all Americans." 

Bush's announcement is sure to reverberate throughout Republican politics and begin to help sort out a field that includes more than a dozen potential candidates, none of whom have formally announced plans to mount a campaign. 

Should he ultimately decide to run, Bush can tap into his family's vast political network and his campaign would attract strong support from the same donor pool that other establishment-minded Republicans -- New Jersey Gov. Chris Christie among them -- need to fuel their own prospective campaigns. 

A Bush candidacy also has the potential to affect the plans of Florida Sen. Marco Rubio, who came up through Florida politics as a strong Bush supporter and is considering whether to seek re-election to the Senate or run for president in 2016. 

Rubio spokesman Alex Conant said Tuesday in a statement: "Marco has a lot of respect for Governor Bush, and believes he would be a formidable candidate. However, Marco's decision on whether to run for President or re-election will be based on where he can best achieve his agenda to restore the American Dream -- not on who else might be running." 

Tuesday's Bush statement is the latest and most definitive signal that Bush plans to try and become the third member of his family to serve as president. In a TV interview this past weekend, he said he "would be a good president," disclosed that he was writing an e-book about his time as governor that would come out in the spring, and promised to release about 250,000 emails from his time in office. 

During his two terms as Florida governor, Bush pushed for large tax cuts, overhauled Florida's education system and led the charge to eliminate race-based policies in college admissions and state spending. 

Since leaving office, Bush has continued to advocate for more changes to the nation's schools, including the adoption of new education standards known as Common Core. Those standards have drawn the ire of conservatives who view them as a federal intrusion into local classrooms, but Bush has continued to call them critical to overhauling the country's education system, while seeking common ground with opponents by saying states should be allowed to develop their own education programs. 

The Associated Press contributed to this report.