WASHINGTON, May 29 (UPI) -- By this time next week, there may be several more candidates on the official list of 2016 presidential hopefuls.
Analysts say O'Malley is hoping to appeal to progressive Democrats -- and rely on 12 years of public service leading Baltimore, as mayor, and the state of Maryland, as governor.
In 2008, he publicly endorsed and campaigned for Clinton. This time around, Clinton is again a candidate -- but O'Malley doesn't feel that she is the best person for the job anymore.
"Governor O'Malley has tremendous respect for Secretary Clinton, but times change," the politician's spokesperson, Haley Morris, said. "We need new leadership to address our nation's big challenges right now -- from the continued law breaking on Wall Street to a broken economy that's leaving too many Americans behind."
O'Malley has been a significant benefactor of the Clintons during past campaigns, as the first couple tapped into their vast network of supporters to raise money for the former Baltimore mayor. O'Malley even chaired the Maryland office of Hillary's 2008 run.
Some political analysts, though, say a lot can change in eight years.
"Let's be honest here. The presidency of the United States is not some crown to be passed between two families," he told ABC News in March, presumably referring to the Clintons and Bushes.
Although every poll has O'Malley trailing Clinton, the former governor's aides don't believe that's an insurmountable deficit. And history proves that they might have reason for optimism.
In 2004, Democratic candidate Howard Dean rode a number of primaries and caucuses to victory, enjoyed tremendous support from his party, and at one point appeared to be a shoo-in for the DNC's nomination. A matter of weeks later, though, Dean had been bucked from the race in favor of a surging John Kerry.
O'Malley, though, won't be the only candidate being watched over the next few days. Several others may also throw their hat into the ring for 2016.
Former Gov. Rick Perry will hold a rally in Dallas on June 4, where he is expected to declare his candidacy. Republican Sen. Lindsey Graham will declare whether he will run at an event in South Carolina on Monday. And former Rhode Island Gov. Lincoln Chafee will announce his intentions on June 3 in Arlington, Va.
So far, there are eight major GOP candidates in the field and two Democrats. This week, former New York Gov. George Pataki and former Pennsylvania Sen. Rick Santorum launched their campaigns for the GOP nomination.