NEW YORK (AP) _ Hillary Rodham Clinton triumphed in her historic quest for the U.S. Senate, defeating Rep. Rick Lazio on Tuesday to become the only first lady ever elected to public office.

The campaign was the longest and costliest race in state history and saw issues of character, place of birth, marital fidelity, and campaign finance collide with discussion of education, Social Security and the state's economy.

But Clinton herself was the main issue in the campaign against the Long Island congressman to replace retiring Democrat Daniel Patrick Moynihan.

Clinton's victory was projected based on interviews with voters as they left polling places. The interviews were conducted by Voter News Service for The Associated Press and five television networks.

Clinton's planning for the Senate race began in the living quarters of the White House in February of last year when she met for several hours with New York political veteran Harold Ickes, a former White House deputy chief of staff during President Clinton's first term. That very day, the Senate voted on whether to remove her husband, an impeachment triggered by his affair with Monica Lewinsky.

By early July, she was at Moynihan's upstate New York farm receiving his blessing and kicking off a summer-long ``listening tour'' of New York. In January, she moved into a $1.7 million house she and the president had bought in suburban Westchester County.

At the time, the likely Republican candidate was New York City Mayor Rudolph Giuliani.

But the ``clash of the titans'' wasn't to be. Giuliani never seemed to warm to the campaign. By mid-May, he was out of the race, battling prostate cancer and beset by marital woes.

Coming off the GOP bench, Lazio literally fell flat on his face, a Memorial Day parade mishap which left him with a fat lip and stitches. But within days, Lazio was running almost even with Clinton in the polls and amassing a campaign war chest that would soon surpass the first lady's own impressive lode.

By mid-October, the two had spent a combined $58.6 million in the race. With the $19 million spent by Giuliani added in, the race became among the most expensive Senate campaigns in history.

Lazio advertised himself as the ``real New Yorker,'' a moderate Republican who traveled the state on a bus called ``The Mainstream Express.'' In fund-raising letters, he denounced the Clintons for ``embarrassing the nation.'' Republican allies said the first lady wanted to use the Senate seat as a stepping stone to run for president.

Clinton repeatedly sought to portray Lazio as out of step with New Yorkers, noting that he had served as a deputy whip under former House Speaker Newt Gingrich.