Hillary Clinton has reached the number of delegates needed to clinch the Democratic nomination for president, The Associated Press reported Monday night.

Mrs. Clinton had been expected to clinch the nomination on Tuesday after polls closed in New Jersey.

But The Associated Press surveyed super delegates on Monday night, and their reporting showed that Mrs. Clinton had secured the overall support of the required 2,383 delegates, according to a news release.

The call comes before voting Tuesday in six states including California, where Senator Bernie Sanders of Vermont was hoping for an upset victory to extend his campaign.

Both candidates had spent the weekend and Monday campaigning in California.

Mr. Sanders, who had vowed to stay in the race until the convention, said in a news conference on Monday that he “hoped to win” in California, but added, “Let’s assess where we are after tomorrow before we make statements based on speculation.”

Mrs. Clinton won the Puerto Rico primary on Sunday bringing her closer to the number of pledged delegates required for the nomination.