Hillary Clinton speaks during a conference in Washington last week. (Melina Mara/The Washington Post)

Presumptive Democratic presidential nominee Hillary Clinton plans to announce a major voter mobilization effort on Monday that will aim to add more than 3 million people to rolls by November to bolster her odds against Republican Donald Trump.

Aides say Clinton plans to formally unveil the initiative during a speech at an NAACP gathering in Cincinnati and will attend an event with volunteers who have been out in the area signing up voters.

The effort is reminiscent of a strategy employed by President Obama in 2008 that helped build his successful coalition, which included a larger turnout of minority and young voters than in previous cycles.

The task has taken on a renewed urgency this election, Democrats say, with a presumptive Republican nominee whose public statements and policy pronouncements have alienated Hispanics and Muslims, groups that have registered to vote at lower rates than the population at large.

The campaign of the presumptive Republican nominee, Donald Trump, is sparking a surge in the number of citizenship applications and voter registrations among Hispanics fearful of his immigration policies. Since January, California alone has seen a boost of 218 percent in Democratic registration and among Hispanics, registration is up 123 percent. (Alice Li/The Washington Post)

Monday’s announcement is timed to coincide with the start of the Republican convention in Cleveland, and the voter mobilization drive is one of several events Clinton has planned this week to counter the Republican Party’s promotion of Trump.

Aides to Clinton said they intend to make voter registration a major focus at every level of the campaign, including among coordinated Democratic drives in key states. This week alone, they said, more than 500 registration-themed events will take place across the country.

In some battleground states, the effort has been underway in less formal ways. Organizers in North Carolina, for example, have focused on signing up both African American voters and those new to the state. North Carolina continues to have a large influx of professionals in the urban and suburban corridor between Charlotte and Raleigh, the state's two largest cities, which Democrats say should help make the state competitive this year.