Feb. 5 (Bloomberg) — Illinois Senator Barack Obama defeated New York Senator Hillary Clinton in Georgia’s primary, networks projected, gaining the first victory on the biggest day of voting in the race for the Democratic presidential nomination.

Obama’s victory in Georgia, where blacks comprise about half of the state’s Democratic voters, was projected by CNN, NBC, Fox and the Associated Press. Obama, who is vying to become the nation’s first black president, won 86 percent of the black vote and 43 percent of white voters, MSNBC said, citing exit polls.

Voters in 22 states participated in today’s Democratic nominating contests; polls in most are still open. New York, Illinois and California are among the day’s biggest prizes, though a candidate can take a portion of the delegates in any state without winning the contest there outright.

Clinton and Obama were essentially tied in a poll of California voters released as balloting began there.

While officials in both campaigns say they expect the battle for the nomination to extend beyond this evening, the balloting may provide more clarity on the race. Before today, Obama and Clinton had each won two of the four contested elections.

Early Polls

Clinton, 60, was leading in polls of voters in most Feb. 5 states until Obama won a landslide victory in South Carolina on Jan. 26. In recent days, Obama closed the gap with Clinton in a number of states or moved ahead; the two are also deadlocked in national polls.

Clinton’s campaign was already looking beyond today’s voting. Her top adviser called for weekly debates with Obama until March 4, when nominating contests are held in Ohio, Rhode Island, Texas and Vermont.

Clinton has accepted four invitations to debate in coming weeks on several television networks, including ABC, CNN, MSNBC and Fox. “We think it’s important that people get to see the two candidates face to face,” Clinton’s chief strategist Mark Penn said on a conference call with reporters today.

Obama hasn’t ruled out debates as the primary battle continues, said David Plouffe, Obama’s campaign manager.

Still, “our schedule is not going to be dictated by the Clinton campaign,” Plouffe told reporters today in Chicago. “We’re going to evaluate the whole schedule really through March 4, and debates will be part of that.”

Delegate Race

A candidate needs 2,025 votes at the Democratic Party convention in August to win the nomination and Obama, 46, was leading in the number of convention delegates elected through primaries and caucuses. Before today, he had 63 to Clinton’s 48, according to The Green Papers, a nonpartisan Web site that compiles election statistics.

Clinton has an edge among so-called super delegates, Democratic officeholders and party officials who get a vote at the convention and aren’t bound by election results. Coming into today, Clinton had 190 of those delegates in her corner, compared with 104 for Obama, according to The Green Papers.

“We expect to maintain our current overall lead in delegates on Feb. 6,” Howard Wolfson, a top Clinton adviser, told reporters on a conference call yesterday. Wolfson predicted that the current round of voting would be “inconclusive” in terms of singling out a front-runner for the nomination.

Plouffe, meanwhile, sent a memo yesterday to reporters saying he expected Clinton to still win California and a larger share of delegates because of “her huge head start” among the Super Tuesday states. “If we were to be within 100 delegates on that day and win a number of states, we will have met our threshold for success,” Plouffe said.

Obama won the first contest of the nominating race, with a victory in the Jan. 3 Iowa caucuses. Clinton then won the Jan. 8 New Hampshire primary and Jan. 19 Nevada caucuses.

To contact the reporters on this story: Kristin Jensen in Washington at kjensen@bloomberg.net ; Ken Fireman in Washington at Kfireman1@bloomberg.net