From the Vault: Continuing to fight for the Democratic nomination

With less than a month left until the last presidential primary, Hillary Clinton holds a nearly-insurmountable delegate lead over her Democratic rival Bernie Sanders. As her campaign frequently points out, her nearly-300 pledged delegate lead is greater than the less-than-200 delegates she trailed Barack Obama at the same point in 2008. Despite the long odds, Clinton refused to suspend her campaign until every state voted, which is one of the reasons Clinton hasn't publicly called for Sanders to get out.

Eight years ago this week, Clinton pledged to "keep making our case" until the end, and she made a controversial comment about staying in the race because so many past primary campaigns ended in June -- including the assassination of Bobby Kennedy in 1968. As TIME's Karen Tumulty explained on Washington Week, Clinton felt "she owes it to the people who feel strongly about this candidacy" to continue, but her campaign surrogates promised "she will not do anything that will damage the nominee."

With Sanders continuing his challenge now, some Democratic leaders are worried that his campaign will harm the likely nominee heading into the fall campaign against presumptive Republican nominee Donald Trump. And speculation now, just as in 2008, is about a potential high-profile role for the runner-up at the Democratic convention.