Former Florida governor Reubin O'Donovan Askew today launched his dark-horse candidacy for the Democratic presidential nomination, saying that he intends to "stick my neck out" and "risk losing votes to try to get elected the right way."

"The challenge is not to win the presidency, but to get there in such a way as to govern," the two-term governor and former chief U.S. trade representative said at a fund-raising gala here tonight. "I have no intention to negotiate away my options."

Askew, 54, the fourth Democrat to enter the 1984 race officially, indicated that he intends to bypass many of the special-interest groups that dominate his party.

Portraying himself as someone who wants to lead the nation through "the great global transition" of the 1980s, Askew announced his candidacy at the National Press Club in Washington this morning and again at the historic territorial governor's mansion in Tallahassee. He then flew to Miami in a small borrowed plane for a $250-a-head fund-raiser. The event, hosted by Gov. Robert Graham and Sen. Lawton Chiles (D-Fla.), kicked off a 10-day series of fund-raisers in which Askew hopes to raise $350,000 to get his lean campaign off the ground.

Askew, who has avoided news conferences and many events attended by the other presidential hopefuls, today positioned himself at the center of the political spectrum, to the right of the other announced Democratic candidates, former vice president Walter F. Mondale of Minnesota and Sens. Alan Cranston of California and Gary Hart of Colorado.

Although respected as governor and a player on the national political scene since 1970, Askew begins the formal stage of his presidential race well back in the pack. A January Gallup Poll found that only one voter in five had ever heard of him and only one in 10 knew anything about him.

"No one is more aware than I am that my name is less than a household word," Askew conceded at his news conference in Washington. "I've never had anything but an uphill fight."

Although Askew was among the group of New South governors who led the region away from the politics of segregation, he is at odds with other Democratic presidential hopefuls on a series of ideological litmus-test issues, including abortion, gay rights, the nuclear freeze movement and "domestic-content" legislation favored by organized labor. He has also called for a "domestic Marshall Plan" to rebuild basic American industry.

Askew also carries the stigma of being a former southern governor like Jimmy Carter, whom he hopes to follow from obscurity into the White House.

"I'm not defensive about working with Jimmy Carter," Askew said today. "But I'm not Jimmy Carter."

Nonetheless, questions about Carter and Askew's positions on abortion, gay rights and labor dogged him during his first day as an official candidate. Askew aides expelled Robert Kunst, a gay activist who claims Askew is "the Moral Majority's Democratic candidate," from the announcement ceremony in Washington.

Askew's political strength is his reputation for integrity and candor, which he underscored yesterday by filing his income tax returns from 1969 to 1981 with the Federal Election Commission and saying that he will not accept any contributions from political action committees. Mondale and Hart also are refusing PAC contributions.

The tax returns showed that Askew paid $6,459 in federal taxes on $25,269 income in 1969 and $92,829 in federal taxes on $287,643 income in 1981.

Askew, a born-again Christian who neither smokes nor drinks and who served orange juice rather than liquor at state affairs as governor, first made his mark in 1972, when he took on conservative party elders and most of the population of Florida over a referendum on the primary ballot that called for a constitutional amendment to outlaw school busing.

Askew stumped the state in an unsuccessful effort to defeat the referendum, and later that year was picked as the keynote speaker at the Democratic National Convention.

However, he rejected overtures from Democratic presidential nominee George McGovern to be his running mate.

As governor, Askew appointed the first black to the state supreme court and the first woman to the state cabinet. He led the successful fight for the state's first corporate income tax and for its "sunshine amendment," which requires full disclosures by candidates and office holders.

Askew has avoided meeting with the media and speaking at events considered "musts" by other candidates, but he has the nucleus of a campaign organization in Iowa and New Hampshire.

Today he announced he had collected $5,000 or more in campaign funds in each of 23 states, which makes him eligible to collect federal matching campaign funds.