2008 2016 Share of all delegates With superdelegates Clinton Obama 50% 50% Without superdelegates 40% 40% 30% 30% Clinton Sanders 20% 20% 10% 10% Feb. March April May June Jan. Feb. March April May June 2016 2008 Share of all delegates With superdelegates Clinton Obama 50% 50% Without superdelegates 40% 40% 30% 30% Clinton Sanders 20% 20% 10% 10% Feb. March April May June Jan. Feb. March April May 2016 Share of all delegates With superdelegates Clinton 50% Without superdelegates 40% 30% Sanders 20% 10% Feb. March April May June 2008 Share of all delegates Obama 50% With superdelegates 40% Without superdelegates 30% Clinton 20% 10% Jan. Feb. March April May Note: Superdelegate counts for 2008 are based on surveys by The Times.

Hillary Clinton leads Bernie Sanders by more delegates than Barack Obama had over Mrs. Clinton in 2008. As of June 6, when The Associated Press announced that Mrs. Clinton had crossed the 2,383-delegate threshold needed to secure the Democratic nomination, she had nearly 300 more pledged delegates than Mr. Sanders and more than 500 superdelegates. After the primaries on June 7, she reached a majority of pledged delegates, increasing her pledged delegate lead to nearly 400.

In 2008, Mr. Obama led Mrs. Clinton by about 100 pledged delegates and 100 unpledged delegates on June 3, the day he was declared the presumptive Democratic nominee.

The Sanders campaign has argued it is wrong to say Mrs. Clinton is the nominee because superdelegates can change their allegiance any time before the Democratic National Convention in July.

However, in 2008, Mr. Sanders endorsed Mr. Obama for president two days after a last-minute rush of superdelegates helped push Mr. Obama over the threshold needed to be nominated at the party’s convention — and before Mrs. Clinton officially dropped out of the race.

Sanders Would Need Hundreds of Superdelegates to Switch Sides to Win

ESTIMATED PLEDGED DELEGATES* SUPERDELEGATES 2,216 571 Clinton Sanders 1,835 48 500 2,383 to win ESTIMATED PLEDGED DELEGATES* SUPERDELEGATES Clinton 2,216 571 Sanders 1,835 48 500 2,383 to win ESTIMATED PLEDGED DELEGATES* SUPERDELEGATES Clinton 2,216 571 1,835 48 500 Sanders 2,383 to win *Projected number if the candidates evenly split the remaining pledged delegates from the contests on June 7 and in Washington, D.C. on June 14.

If Mr. Sanders and Mrs. Clinton evenly split the remaining pledged delegates, Mr. Sanders would still need to win the remaining 95 superdelegates and convince about 400 of those pledged to Mrs. Clinton to shift their support to him.

The Popular Vote Was Also Closer in 2008

Mrs. Clinton did not leave the race immediately after Mr. Obama passed the threshold of delegates needed to secure the nomination (she waited four days). Like Mr. Sanders, she presented the case that she was the stronger candidate. She also argued that she had won the popular vote, a notion disputed by the Obama campaign and that hinges on whether you count votes from Michigan, where Mr. Obama’s name did not appear on the ballot. According to factcheck.org, both candidates received roughly 18 million votes and, any way you slice it, the totals are within less than 1 percent of each other.