Last Thursday, C. Virginia Fields began the day with a fund-raising breakfast for her mayoral campaign in Midtown Manhattan and finished the day with a downtown fund-raising event. But the second event wasn’t in downtown Manhattan or downtown Brooklyn.

It was in the heart of downtown Atlanta.

Raising money at a restaurant more than 850 miles from New York’s City Hall, from donors who do not live or work at the five boroughs, might seem counterintuitive – especially since Manhattan includes the top five fundraising Zip codes in the country, according to the Web site of the Center for Responsive Politics.

But Ms. Fields, the Manhattan borough president, is not the only mayoral candidate looking to other cities and states for campaign funds this year.

At least two of the four Democrats in the race, Ms. Fields and a former Bronx borough president, Fernando Ferrer, are going national. So is Thomas Ognibene, the former Republican minority leader of the City Council, who is challenging Mr. Bloomberg for the Republican nomination.

“Funding for politics nationally is becoming much more of a national phenomenon,” a professor of public affairs at Baruch College, David Birdsell, said. He said that’s especially true for New York candidates since New York City has significant national appeal.

The former public advocate, Mark Green, who ran against Mr. Bloomberg in 2001, said asking out-of-towners for money makes more sense this year than before because the candidates must compete with a self-financed billionaire.

“Normally you wouldn’t have to focus on that, because there’s enough money in New York to amply fund the primary and general election,” Mr. Green, who hopes to run for New York attorney general next year, said in a telephone interview. “Bloomberg makes out-of-town fundraising in the general election more crucial.”

The mayor’s deep pockets are driving Mr. Ognibene outside the city for contributions, the former city councilman from Queens said in an interview, even though donations from non-residents aren’t eligible for matching funds. Mr. Ognibene met Friday with his chief fund-raiser and campaign manager, Brendan Quinn, to craft a national fund-raising strategy.

“We think that Mr. Bloomberg’s record will resonate in a negative way nationally,” Mr. Ognibene said. “We think probably the pro-life groups, and those who believe in all the traditional values of the Republican Party believes in, will be supportive of my candidacy.”

Mr. Bloomberg’s other Republican opponent, Steven Shaw, an investment banker, said he would stay closer to home.

“I think the people who are most likely to contribute are the people who are going to be impacted most by the decisions the candidate would make, and obviously those are people who live in the five boroughs, not people who live in California,” Mr. Shaw, an investment banker, said.

Campaign officials representing the four Democrats all said most of their contributions would come from New York City. Spokesmen for the City Council speaker, Gifford Miller, and for Rep. Anthony Weiner said virtually all of their candidates’ contributions would come from New Yorkers.

Mr. Miller’s campaign spokesman, Reggie Johnson, said: “Virtually all of our contributions come from people who live and work in New York City. Through their support, we have been able to raise more money than any other mayoral campaign and have now started to focus our fund-raising efforts on challenging Mayor Bloomberg.”

Mr. Weiner’s spokesman, Anson Kaye, said the congressman is targeting individuals and small businesses in the outer boroughs, although he said Mr. Weiner would get some national support from Jewish groups.

Mr. Birdsell said Mr. Weiner and Mr. Miller are probably keeping their fundraising local out of necessity and can be expected to argue in the coming months that national interest groups are trying to buy influence with their political opponents.

“It’s hard to imagine what network Weiner and Miller would tap into at this point,” the Baruch professor said. “There isn’t the ‘Elect Another White Guy’ fund out there.”

There are, however, national groups and individuals that support black candidates, Latino candidates, and female candidates.

Ms. Fields’s consultant, Joseph Mercurio, said Ms. Fields would happily accept donations from across the country, and he said she has a natural appeal to “anybody, anywhere who believes that a woman should be mayor.” The campaign is thinking of putting together events in Birmingham, San Francisco, and Boston.

The chairwoman of Atlantans for Fields, Julia Frazier White, said it makes perfect sense for Georgians and other non-New Yorkers to write checks to the Manhattan borough president.

“I believe it’s important to have good people at every level of government, whether it’s my city, which I believe in, or your city,” she said. “I think it’s very, very important. And the job of mayor to me is a national-level job.”

Mr. Ferrer, too, plans to raise money nationally. His campaign officials have planned fund-raising events at Chicago, Los Angeles, Washington, and Miami in the coming months, though a spokesman said New York money is far more important to the campaign than out-of-town dollars.

“We’re gratified by the strong financial support Fernando Ferrer is getting from people across New York City,” his spokesman, Chad Clanton, said. “This local support and his vision help make the case nationally why Mr. Ferrer is the Democratic Party’s best chance to beat Mayor Bloomberg.”

Mr. Mercurio, of the Fields campaign, said: “The reality in politics is it costs money to communicate. Radio and television is very expensive in New York. Direct mail is expensive everywhere.”