Voters in the District of Columbia could hand Hillary Clinton a final, largely meaningless victory in the last primary election of the 2016 presidential campaign season.

The primary in the nation's capital is Tuesday. Bernie Sanders held a campaign rally in the District last week, the same day President Barack Obama and other leading Democrats endorsed Clinton after she clinched the nomination.

Clinton is expected to fare well in the District, which is 49 percent black. She has defeated Sanders handily in states with large African-American populations.

Clinton and Sanders plan to meet on the night of the final presidential primary.

The Vermont senator has vowed to do all he can to prevent Republican Donald Trump from reaching the White House but suggested he will not endorse Clinton immediately. Sanders said the private meeting will help him determine how committed Clinton will be to the policy issues he has staked out during his 13-month campaign.

In local races, District voters will decide whether former Mayor Vincent Gray will return to the D.C. Council. Gray lost his bid for a second term as mayor in 2014 amid a federal investigation of his 2010 campaign.