Updated

A first-term black congresswoman running on a shoestring campaign and a wealthy white businessman recruited to run by former President Jimmy Carter (search) will meet in three weeks in a runoff for the Democratic nomination to succeed their party's retiring maverick Sen. Zell Miller (search).

Rep. Denise Majette (search), a former judge who won national attention two years ago by ousting firebrand Rep. Cynthia McKinney (search), finished first in Tuesday's election, leading millionaire entrepreneur Cliff Oxford (search), but she failed to reach the 50 percent threshold needed to win the nomination outright.

The winner will face a stern test in November against Republican nominee Rep. Johnny Isakson (search) in a state which increasingly leans Republican. Isakson, a veteran Georgia politician who replaced House Speaker Newt Gingrich (search) in Congress, defeated two rivals to win the GOP nomination outright.

In North Carolina, former Clinton chief of staff Erskine Bowles (search) faced no opposition and five-term GOP Rep. Richard Burr (search) cruised to the nomination in the race for Democratic vice presidential candidate John Edwards' Senate seat. Two Republicans advanced to a runoff to face Democratic Gov. Mike Easley (search), who easily won his primary.

In another Georgia primary, McKinney, a firebrand who lost her House seat two years ago to Majette in a backlash spawned by her incendiary remarks about President Bush, won a chance to take her old seat back in an Atlanta suburb. She beat five other Democrats with enough votes to avoid a runoff.

Majette took 41 percent to Oxford's 21 percent to force the runoff in her race. If she wins, she would be the state's first black Senate nominee.

Democrats had been unable to attract a top-name candidate. Oxford, with his ability to self-fund the effort, was recruited by several top national Democrats, including Carter.

Isakson fended off challenges from black businessman Herman Cain and fellow Congressman Mac Collins to win his primary without a runoff. Isakson approaches the November election as "almost a prohibitive favorite," said University of Georgia political science professor Charles Bullock.

"He's skilled, he's experienced, he's going to have plenty of money. This is going to be a state that votes for George Bush. All the arrows are pointing in his direction," Bullock said.

With 99 percent of precincts counted, Isakson had 53 percent to Cain's 26 percent and Collins' 21 percent. Isakson had been the race's favorite for months and raised as much money as his two rivals combined. The only question had been whether he would win without a runoff.

Cain, the former CEO of Nebraska-based Godfather's Pizza and only the second black to seek a top statewide position in Georgia on the Republican side, wowed GOP audiences with a rock-ribbed conservative message and forceful speaking style. "We have instilled hope in the hearts of a lot of people who had given up the process," he said. "The fact that some people now have hope in the system is worth more than anything else that we can talk about."

The door is open this year for Republicans to make gains in the South. John Breaux of Louisiana, Bob Graham of Florida, and Fritz Hollings of South Carolina are other Democrats who are leaving the Senate. Republicans control the Senate 51-48, with one Democratic-leaning independent.

North Carolina had a full slate of races, including a special election to fill the remainder of the term of former Democratic Rep. Frank Ballance, who resigned for what he said were health reasons but also was under investigation over the handling of funds at a foundation he started.

Former Charlotte Mayor Richard Vinroot and former state Sen. Patrick Ballantine were the top two vote-getters in the state's Republican gubernatorial primary — each capturing about 30 percent of the vote. They are headed for an Aug. 17 runoff.

"After all the numbers are in, we can all celebrate together," Ballantine told supporters. "I want to carry the banner for the Republican Party and win this runoff election."

House co-Speaker Richard Morgan survived a tough GOP primary battle that highlighted a feud that has split the state party. Conservatives said Morgan sold out to broker a power-sharing agreement with Democrats that made him co-speaker.