Jim Cole, Associated Press
Former Maryland Gov. Martin O'Malley, right, talks with New Hampshire State Rep. Bob Backus, left, and former State Sen. Peter Burling before a private meeting with New Hampshire Democrats, Wednesday, May 13, 2015, in Concord, N.H.

WASHINGTON — Former Maryland Gov. Martin O'Malley plans to announce his decision on a presidential campaign May 30 in Baltimore, preparing for what would be a long shot bid against Democratic Hillary Rodham Clinton.

O'Malley would enter the 2016 race as a relatively unknown figure nationally and face a steep climb against front-runner Clinton. O'Malley, an ex-Baltimore mayor who has visited early-voting states, has tried to present himself as a champion of progressive causes and a fresh face for liberals hesitant to support Clinton.

O'Malley was holding a Thursday night conference call with top supporters to provide an update and discuss plans for the announcement. His plans were described by an aide who was not authorized to publicly discuss internal planning and spoke on condition of anonymity.

"My timeline for a while has been by the end of May and that remains my timeline. So stay tuned," O'Malley told reporters Wednesday in New Hampshire, home of the nation's first presidential primary. O'Malley's announcement date was first reported by The Washington Post.

Holding the announcement in Baltimore could carry risk.

O'Malley's record as city leader a decade ago has faced scrutiny since rioting broke out following the death of Freddie Gray in police custody. O'Malley, mayor from 1999 until he was elected governor in 2006, has defended his work to curb violent crime in Baltimore and signaled it would play a leading role in a presidential campaign.

O'Malley frequently talks about his record in Maryland: supporting gay marriage and gun control, ending the death penalty, providing in-state college tuition for immigrants living in the U.S. illegally. He has outlined a potential 2016 that would focus on economic inequality, immigration, campaign finance reform and national security.

Already in the race is Vermont Sen. Bernie Sanders, an independent who has courted liberal voters in the party. Former Rhode Island Gov. Lincoln Chafee and former Virginia Sen. Jim Webb also might run. Each of the Democrats looking to challenge Clinton is hoping to become a viable alternative for Democrats who want a competitive primary.

Rather than directly criticize Clinton, the 52-year-old O'Malley has tried to portray himself as a fresh face representing a new generation of leadership.

During an event in Durham, home of the University of New Hampshire, O'Malley was asked what his presidency might offer to the aspirations of women.

O'Malley noted that Democrats helped make history by electing the nation's first black president, Barack Obama, and he cited his policies in Maryland that he said have benefited women.

While some voters may want to elect the first female president, O'Malley said there is also "a yearning of the next generation of Americans who want a new perspective and ... to solve those problems with new leadership and new perspective."

Dudley Dudley, who held the event at her home, said in an interview that O'Malley would face a "daunting" challenge against Clinton. "It would take some quite amazing turn of events certainly to affect her support here in New Hampshire," she said.

Dudley said she was not prepared to endorse O'Malley but would watch him closely.

"I'm not ready to sign in blood but I liked him very well and certainly wish him very well and will watch him evolve," she said.

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