The former Maryland governor wants more than six debates.
Outside groups say the DNC is rigging the primary by limiting less well-known candidates' chances.
O'Malley urged the party not to "circle the wagons" around the front-runner.
The Democratic presidential candidate also addressed the AFL-CIO on Wednesday.
O’Malley said the “electorate actually looks at candidates in a very holistic way.”
"These are not ideas that excite the electorate,” he said.
When activists take up confrontational tactics, it's not to make media appearances, but to shed...
Martin Luther King III will use 50th anniversary of Voting Rights Act to call for reforms.
The Republican National Committee gleefully blasted out the poll results.
The trip makes him the first presidential candidate to campaign there in the 2016 election cycle.
Rep. Eric Swalwell, a California Democrat, will support O'Malley for president.
Martin O'Malley cowered to the new rules of the road for the politically correct left.
O'Malley said he was "flattered" by the email.
“One debate in Iowa. That’s it. One debate in New Hampshire. That’s all we can afford.”
"We need to have start having debates about the issues," he said.
The trend leftward just reached a new level.
The former governor has sought to position himself as the most policy-minded candidate.
“They really are speaking to the issues," Rep. Sheila Jackson Lee (D-Texas) said.
His attorney called the DNC's rules “unenforceable” and “legally problematic."
O’Malley lit into the Democratic Party during exclusive interview with The Hill.
The pitch comes days before the 50th anniversary of the Voting Rights Act.
"We cannot let this become the new normal," he said of recent mass shootings.
The Democrat tries to get traction on the issue of Wall Street reform.
The GOP pounced on the remarks, with RNC chief Reince Priebus calling them "absurd."