But as he ponders the biggest decision of his young political career, the mayor is also getting an earful of reasons not to run.
From philanthropic leaders: If you stay at City Hall, we'll increase our support of the city.
From business executives: If you leave City Hall, there's no one ready to take your place right away.
And from elected officials: Finish the job you started in Baltimore. If you take on Lt. Gov. Kathleen Kennedy Townsend for the Democratic nomination, you'll only do damage to yourself, the party and the city.
"If he runs and loses, he will be perceived as a spoiler," said Del. Howard P. Rawlings, who endorsed O'Malley's 1999 mayoral run and, as chairman of the House Appropriations Committee, is one of the city's most powerful representatives in Annapolis.
O'Malley, in his latest round of should-I-or-shouldn't-I musings in an interview hours before yesterday's fund-raiser, made clear that he doesn't see himself as a potential spoiler.
"I don't doubt that I can win, but I really love what I'm doing. That's the hardest part. We've gotten a lot done in two years, and you can see the difference," O'Malley said. "But I don't doubt that I can win."
Last night's event didn't appear to dampen that confidence. With roughly 1,700 people paying $250 or $1,000 each, O'Malley raised more than $1 million in one evening, an outsized fund-raiser for a not-quite-candidate for governor in Maryland.
O'Malley was introduced by a potential running mate, Prince George's County Executive Wayne K. Curry.
And the event was packed with political and business leaders with divergent views on whether he'll run.
Some advisers are citizens on the street, telling him to go for it. Others, like the Interdenominational Ministerial Alliance, which recently urged O'Malley not to run, are vehement critics with political motives of their own.
Still others are career politicians with a clear agenda, having chosen to back O'Malley's potential Democratic opponent, Townsend.
On Monday, for example, O'Malley paid a visit to Montgomery County Executive Douglas M. Duncan to try and dissuade him from a public endorsement of Townsend planned for yesterday. Duncan gave the mayor his advice.
Some prominent state lawmakers from Baltimore have given the mayor the same advice and have worked since as early as December to keep O'Malley out of the governor's race. Most legislators from the city, as well as from across the state, are backing Townsend's bid for governor.