The Republican and Democratic candidates for governor campaigned across Fairfax County yesterday, saying the state's most populous jurisdiction is becoming the pivotal battleground that will decide who leads Virginia.

Both candidates appeared with other prominent politicians at their sides.

Lt. Gov. Timothy M. Kaine, the Democratic candidate, spoke at a labor union rally and in the Annandale fall parade with Gov. Mark R. Warner and Fairfax Board of Supervisors Chairman Gerald E. Connolly, fellow Democrats.

Republican candidate Jerry W. Kilgore, the former attorney general, was accompanied by U.S. Sen. George Allen (R-Va.) at a private barbecue in Vienna.

Both candidates claimed to have momentum on their side as the Nov. 8 election approaches.

"The race is a dead heat now," Kaine said at an Annandale rally attended by union members wearing jackets and shirts identifying themselves as ironworkers, Teamsters and glaziers. Kaine said that polls a few months ago showed him trailing Kilgore and that they now show him ahead by a slim margin, adding, "We have momentum when we wanted it, at the end."

At the barbecue, hosted by Robert McDowell, a longtime friend and party activist, Kilgore said the very fact that Kaine is campaigning in Northern Virginia just before the election shows the Democrat is lagging.

"The battleground is in Northern Virginia, and that's a victory for me," he said. "We're going to win by a good majority in the exurbs, and our goal is to get in Fairfax County and win."

Fairfax is not only the biggest jurisdiction in Virginia, but it also has a history as a bellwether.

One in seven Virginians lives in the county, and it is the only county in the state that has swung for the winner in every gubernatorial election, Connolly said.

"You can't win in the state without a strong performance and a win in Fairfax County," said Kaine, who placed his statewide get-out-the-vote headquarters in the county.

Connolly said many voters see a Kaine governorship as a continuation of the Warner administration and predicted Kaine would carry Fairfax. Virginia governors are barred from succeeding themselves.

"Mark has been a very successful governor, and people want to keep that going," Connolly said. "Tim is the logical successor. He represents a continuation of that success and going forward. Kilgore would be an abrupt departure, back to the days when the state was in a rut and its bond ratings were put on a watch list."

Allen said Kilgore's positions resonate more with Virginia voters.

"Ultimately, Virginians will decide which of the two candidates is closer to their values and the trustworthiness they expect in a governor," he said. "If they're concerned about tax increases, they'll vote for Jerry Kilgore. If they want tax increases, they'll vote for Tim Kaine. Among law enforcement and criminal justice people, Jerry has a great record. On illegal immigration, Jerry's position is closer to mine and most Virginians."

During their day in Fairfax, both candidates were surrounded by enthusiastic supporters.

Kaine, who spent a year as a missionary in Honduras, occasionally spoke Spanish when meeting Latino voters.

"It was very moving," said Raymin Diaz, 22, an immigrant from the Dominican Republic who attended the union rally where Kaine said to them in Spanish that Kilgore's positions inflamed passions against recent immigrants. "I felt he would definitely look out for the concerns of all of us, both English- and Spanish-speaking."

When Kaine arrived for lunch at the Vienna Inn along with Leslie L. Byrne, the Democratic candidate for lieutenant governor, many diners stood up and applauded him. Several photographed him with their cell phone cameras as he worked the crowd, pausing to ask voters their names and genially posing with his arm around their shoulders.

About 200 invited supporters showed up at McDowell's Vienna home to see Kilgore and his wife, Marty, who had spent the morning marching in the Annandale parade.

Supporters Judi Nardella and Michael Hershman of McLean said they have seen more lawn signs for Kilgore than ever for a candidate in a gubernatorial election.

"I sense a lot of energy in our base," McDowell said. "They're eager to show Jerry Kilgore is a terrific guy, both smart and honest."

Lt. Gov. Timothy M. Kaine (D)works the crowd at a parade in Annandale. "The race is a dead heat now," Kaine said.Republican candidate Jerry W. Kilgore campaigns at a private barbecue fundraiser hosted by a friend.