Vice President Kamala Harris has canceled a planned campaign appearance alongside California Gov. Gavin Newsom aimed at boosting Democratic turnout in the final weeks of the recall election that could force him out of his job.

The vice president’s decision to cancel her trip to her native state followed attacks in Afghanistan that killed at least 12 U.S. service members. She and Newsom were set to appear at a rally south of San Francisco.

Spokespeople for Harris did not immediately answer questions about whether she would reschedule the trip. It was also unclear whether President Joe Biden would travel to California to campaign for Newsom amid the ongoing events in Afghanistan. White House Press Secretary Jen Psaki said Wednesday, before the attacks, that Biden planned to do so.

The president’s and vice president’s plans to campaign for Newsom underscored the closeness of the race and its potential to significantly alter the political landscape in the nation’s most populous state.

Voters last elected a Republican to statewide office in 2006. About one-tenth of the 22 million registered voters in California have already cast ballots. The last day to vote is Sept. 14.

At this point, a visit from Biden could do more harm than good for both he and Newsom because of the unfolding situation in Afghanistan, said Sherry Bebitch Jeffe, a professor of public policy communication at the University of Southern California.

“I don’t see any reason, on either end, that it’s absolutely necessary, let alone positive, for the president to take time to go campaign for Gavin Newsom right now,” she said.

She similarly said it was smart for Harris to cancel her trip, though it would have drawn attention and excitement from some Democrats.

Californians elected Harris statewide three times, first as attorney general and later a U.S. senator. Newsom in recent weeks has focused his campaign messaging on women and voters of color, groups that Harris is uniquely poised to speak to as the nation’s first woman vice president, as well as the first Black and South Asian person to serve in that role.

Should voters recall Newsom, they have the chance to elect the state’s first Black governor: Talk radio host Larry Elder, who is running as a Republican. In recent weeks, Newsom and his Democratic allies have focused almost exclusively on Elder, warning his libertarian and conservative policies would be wrong for California. On a Tuesday campaign call, Black women leaders argued Newsom is a better ally to the Black community than Elder.

Harris and Newsom began their political careers in the same San Francisco political circles. Harris’ was the city’s district attorney in the early 2000s when Newsom served as its mayor. They have never competed against each other for political office, and they share donors and political consultants.

Democrats have tried to nationalize the race, linking the recall effort to Republicans including former President Donald Trump, who has not publicly commented on the contest.

Republicans, meanwhile, have tried to keep the race focused on California issues and what they consider to be Newsom’s failures in tackling homelessness, crime and wildfire prevention.

The nation’s withdrawal from Afghanistan has not been a topic of discussion.