Two-term New Hampshire Sen. Bob Smith lost a bitter GOP battle to Rep. John Sununu on Tuesday, while Janet Reno's bid for the Florida Democratic gubernatorial nomination faltered against a surprisingly aggressive political newcomer.

Smith was the first elected senator to lose a primary in a decade.

In the race for Jesse Helm's Senate seat in North Carolina, Elizabeth Dole easily defeated six other candidates to win the GOP nomination. She will face Democrat Erskine Bowles, former chief of staff in the Clinton administration.

In a third crucial race for the fall, Democratic Sen. Paul Wellstone and Republican Norm Coleman easily won their primaries in Minnesota.

In Florida, McBride had 432,784 votes, or 49 percent, with 63 percent of precincts reporting; Reno had 344,107, or 39 percent. Barely a quarter of the vote was counted in three South Florida counties where she hoped to run strong.

In New Hampshire, Sununu had 68,415, or 54 percent, to Smith's 56,665, or 45 percent, with 88 percent of precincts reporting. In North Carolina, Dole got 328,253 votes, or 81 percent, with 95 percent of precincts reporting. Bowles, a Charlotte investment banker, had 262,719 votes, or 44 percent. His nearest challenger, State Rep. Dan Blue, had 171,384, or 29 percent.

In the busiest primary day of the year, voters in 12 states determined fall lineups for six open governor's offices, three of the most competitive Senate seats and a few House seats that could influence control of Congress and the shape of the next two years of President Bush's administration.

There were also races in Arizona, Connecticut, Maryland, New York, Rhode Island, Vermont, and Wisconsin. Georgia held runoffs.

In an echo of voting problems two years ago, Florida's polling hours were extended two hours because of widespread voting problems in the first test of the state's revamped elections system. Polling places opened late, and workers had problems starting up new touchscreen voting machines and running other ballots through scanning machines.

Reno's campaign warned of the possibility of a post-election battle. "When that many people are turned away from the polls, it raises enough concerns that we're going to have to take a good, hard look at the legitimacy of the election," said campaign manager Mo Elleithee.

Former Florida Secretary of State Katherine Harris won the GOP primary for an open House seat in a safely Republican district.

Reno saw her wide lead in the polls shrink to a too-close-to-call race as McBride won party endorsements and raised more cash.

State party leaders, who had hoped for an aggressive challenge to GOP Gov. Jeb Bush after the 2000 presidential election crisis, said McBride would stand a better chance of defeating the president's brother in the fall.

Reno had angered many in Florida's Cuban community, an influential voting bloc, when as Clinton's attorney general she oversaw the federal raid two years ago that took Elian Gonzalez from his Miami relatives. The boy was sent back to Cuba with his father.

In New Hampshire, Sununu, a three-term congressman, will face three-term Democratic Gov. Jeanne Shaheen, who was unopposed.

Sununu is the son of former Gov. John H. Sununu, who was chief of staff to the former President Bush.

Smith was the first elected senator in a decade to be unseated in a primary. In 1992, Illinois Democrat Alan Dixon lost to Carol Moseley Braun, who went on to serve one term as the nation's first black woman senator.

Smith faced a backlash for briefly quitting the party in 1999 for a failed presidential run. Some critics said Sununu would do better against Shaheen; others said they couldn't forgive him for bolting the party, even though he returned a few months later.