Spotlight: As U.S. mainstream media ready to call the nomination race, Bernie Sanders demurs

As U.S. mainstream media were about to call the race for Democratic presidential candidate Hillary Clinton on next Tuesday, Bernie Sanders, Clinton's rival in the nomination race, said otherwise.

"The media is in error when they lump superdelegates with pledged delegates," said Sanders at a press conference on Saturday in Los Angeles, California. "Hillary Clinton will not have the requisite number of pledged delegates to win the Democratic nomination at the end of the nominating process on June 14."

Vowing to continue his fight for nomination beyond the primary season, Sanders predicted that the Democratic National Convention "will be a contested convention."

As of Saturday, Clinton led Sanders in pledged delegates count with 1,769 to 1,501, according to the latest New York Times tally.

To win the party nomination, any candidate needs 2,383 delegates in total.

While Clinton was widely viewed as unlikely to expand her pledged delegates over the threshold of 2,383 next Tuesday, when six of the remaining seven Democratic nomination races will be held, U.S. cable news, such as CNN, had already predicted that she would clinch the nomination soon with the help of unpledged delegates, or superdelegates.

In an earlier TV program broadcasted in late May, MSNBC host Chris Matthews also revealed that major U.S. TV networks were planning to call the Democratic primary for Clinton on June 7, hours before the close of polls in California.

"I'm told by the experts on numbers around here are NBC and elsewhere that come June... that at 8 o'clock that night, Eastern time, the networks will be prepared, including this one, to announce that Hillary Clinton had now gotten over the top, that she will have won the nomination in number, it's done," said Matthews then to Sanders' campaign manager Jeff Weaver.

However, Debbie Wasserman Schultz, the chair of the Democratic National Committee (DNC), had for long urged the U.S. mainstream media not to count superdelegates in there reports.

"Combining them (pledged delegates earned in state-by-state race and superdelegates) at each phase of this contest is not an accurate picture of how this works," said Wasserman Schultz in an interview with MSNBC in February.

In the Democratic field this election cycle, the 714 superdelegates, unpledged Democratic Party leaders who are free to support any candidate, can make their final decision at the national convention in July. So far, an overwhelming majority had declared support to Clinton.

"The way the media is reporting this is incorrect," said Wasserman Schultz.

Though admitting that it was uphill battle, Sanders had repeatedly argued that he would be able to persuade some superdelegates to switch allegiance.

Apart from leading Sanders in the number of pledged delegates and superdelegates, Clinton also leads the race in the number of votes cast. However, Sanders' one advantage over Clinton is hard to ignore.

According to PolitiFact.com, a project dedicated to "fact-check" of statements of politicians and the federal government, Sanders fared better against Trump than Clinton did in all polls over the last six weeks.

On Sunday, a new poll released by CBS News also found that while Clinton leads Trump in a hypothetical matchup with 48 to 33 percent in California and 49 to 34 percent in New Jersey, Sanders leads Trump by larger margins of 23 and 18 percent in the two states respectively. Endit