Jeb Bush is (almost) in for 2016.

The former two-term Republican governor of Florida announced Tuesday morning on Facebook and Twitter that he had decided to "actively explore the possibility" of running for president. As the son of President George H.W. Bush and brother of President George W. Bush, he would extend an unprecedented White House dynasty if he becomes the third member of his family in the last 30 years to win the presidency.

In the form of a holiday greeting, Bush wrote on Facebook that he had discussed a possible candidacy with his wife, Columba, and their family over Thanksgiving. "As a result of these conversations and thoughtful consideration of the kind of strong leadership I think America needs," he wrote, "I have decided to actively explore the possibility of running for president of the United States."

Bush said he would establish a political action committee in January to support candidates and to "facilitate conversations with citizens across America to discuss the most critical challenges facing our exceptional nation." The announcement comes amid a flurry of political activity for Bush, who flirted with a presidential bid in 2012 but had been seen as reluctant to dive back into the rough-and-tumble of electoral politics more than a decade after he last ran for office. While Bush's older brother has been a cheerleader for his possible bid, his mother, former First Lady Barbara Bush, has famously dismissed the idea, saying "we've had enough Bushes."

Delivering a winter commencement address in the early primary state of South Carolina on Monday, Bush steered clear of politics, but urged graduates, "Don't be afraid to shake things up." He added, "You don’t have to follow the pattern," according to The Washington Post. “You can do what you want to do. In fact, life is a lot better if you can find more reasons to do your own things.” Perhaps the biggest clue to his intentions came on Sunday, when he said he would write a book and release some 250,000 emails from his tenure as Florida governor.

If he takes the next step of launching a formal bid, his candidacy would test not only the resilience of the Bush brand, but whether a Republican who has backed sweeping federal reforms on immigration and education can win primaries that have historically been dominated by conservative voters hostile to those positions. More recently, Bush has drawn scrutiny for his business dealings and the vast wealth he's accrued since leaving the Florida statehouse in 2007.

Bush would begin a race with the advantage of high name recognition, and a McClatchy-Marist poll released on Monday showed that without Mitt Romney in the field, Bush would lead Mike Huckabee, Chris Christie, and a crowded group of potential contenders. (Romney led Bush when he was included in the poll, but a third run by the 2012 GOP nominee seems even less likely than it already was if Bush enters the race.)

Bush is by the far the biggest name in either party to make any formal announcement about the 2016 race. Christie and Senators Rand Paul and Ted Cruz are considered likely to run on the Republican side, while Hillary Clinton remains the prohibitive Democratic frontrunner if and when she announces her candidacy. Former Senator Jim Webb announced earlier this month that he would form an exploratory committee in advance of a possible run for the Democratic nomination.

Mo Elleithee, a spokesman for the Democratic National Committee, poked fun at the wording of Bush's statement, saying it was little different from when he acknowledged he was "thinking" about a White House run earlier in the year. Turning to substance, Elleithee sought to link Bush to a Republican Party that he said prioritized the wealthy over the middle class.  "There’s no parsing this simple fact," he said in a statement, "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.”