Former South Carolina governor David Beasley and three-term Rep. Jim DeMint advanced yesterday to a runoff for the Republican nomination to seek an open Senate seat, in what is sure to be one of the fall's most closely watched races.

With nearly all ballots in, Beasley had 37 percent, or 107,310 votes. DeMint had 26 percent, or 77,315 votes in the race for the seat left open by the retirement of Democratic Sen. Ernest F. "Fritz" Hollings. Education Superintendent Inez Tenenbaum won the Democratic primary.

The race -- for one of five Democrat-held Senate seats in the South to come open this year -- will be among the most closely watched in the fall, since the GOP narrowly controls the Senate, 51 to 48.

When Hollings announced his retirement after nearly four decades, it set off a GOP scramble among six candidates. In a state that has grown increasingly Republican, the opportunity seemed clear. Beasley quickly became the front-runner, but opponents who helped defeat him in 1998 after one term as governor dogged his latest campaign, criticizing his efforts to lower the Confederate flag and ban video poker when he was in office.

To avoid a runoff, the winning candidate needed to get more than 50 percent of the primary vote.

The state's often fractious Democrats united around Tenenbaum, who portrayed herself as independent-minded and emphasized votes she has gotten from both Republicans and Democrats.