Then-Maryland governor Martin O’Malley addresses the Democratic National Convention in Charlotte, N.C., in September 2012. In South Carolina on Saturday, O'Malley hinted at themes of a possible 2016 presidential bid. (J. Scott Applewhite/AP)

MYRTLE BEACH, S.C. -- Former Maryland governor Martin O’Malley signaled here Saturday that Wall Street regulation would be a major issue in his potential presidential bid, urging Democrats to fight for their principles on that and other defining issues.

“If a bank is too big to fail without harming the common good of our nation, then it’s too big and we must break it up before it breaks us,” O’Malley said in an address to about 300 Democrats gathered here for an annual “Issues Summit.”

His remarks, warmly received by an audience in an early presidential nominating state, come as O’Malley weighs a long-shot bid for the 2016 Democratic nomination. He is widely expected to try to run to the left of Hillary Rodham Clinton if both move forward.

Though Clinton holds commanding leads in early polls, some Democratic activists have expressed qualms about her close relationship with the financial sector. There is a sizable contingent in the party cheering for a bid by Sen. Elizabeth Warren (D-Mass.), a leading critic of efforts in Congress to weaken the 2010 Dodd-Frank law, which was intended to help lessen the risk of another financial crisis. Warren has said she has no plans to run.

Following his speech, in which he made no explicit mention of Clinton or Warren, O’Malley told reporters that Democrats “can’t let ourselves become the party of Dodd-Frank-lite.”

“Trying to find ways to make sure that nobody’s feelings are hurt when we talk about reinvigorating and making more robust the regulation of Wall Street so that rank speculation and gambling with other people’s money does not once again wreck our economy and our common good, you have to be very clear about the beliefs we share and the best way forward,” he said.

Saturday’s remarks were O’Malley’s first political speech since last year’s mid-term elections, a bruising experience for Democrats. Among the casualties was his preferred successor in Maryland’s race for governor. O’Malley said that one of the lessons of 2014 is that Democrats need to be clear about what they believe in.

“Triangulation is not a strategy that will move America forward,” O’Malley said, referring to a term for compromise that was coined during the presidency of Bill Clinton. “History celebrates profiles in courage, not profiles in convenience.”

O’Malley also cited his dust-up with the White House last summer over the plight of migrant children streaming over the border from Central America. At the time, O’Malley accused the Obama administration of being too eager to return the children.

“When refugee children arrive on our doorstep, fleeing starvation and death gangs, we don’t turn them away,” O’Malley told his audience Saturday. “We act like the generous, compassionate people we have always been.”

O’Malley also said that same-sex marriage should be a “human right” and not left to the states.

O’Malley’s effort to legalize same-sex marriage was among several of his accomplishments in Maryland that he touted in Saturday’s speech, in which he also urged talked about the need to end wage stagnation.

While in South Carolina, O’Malley had other private events planned, including a fundraiser Saturday night in Charleston being hosted by trial lawyer W. Mullins McLeod Jr.

O’Malley has appearances scheduled in coming weeks in New Hampshire and Iowa, two other early nominating states.

When speaking to reporters, he reiterated his plans to make a decision about whether to move forward with a presidential bid by spring.

“By the spring, anyone who’s a challenger and intends to win, should be in this, and so by spring I will have made up my mind,” he said.