Hillary Rodham Clinton will launch her long-awaited 2016 presidential campaign on Sunday.

That's according to people familiar with Clinton's plans, who spoke on condition of anonymity because they were not authorized to discuss them publicly.

The former secretary of state is making her second presidential bid, entering the race in a strong position to succeed President Barack Obama as the nominee of the Democratic Party.

If elected, the former first lady would be the nation's first female president.

Any challenge for the Democratic nomination?

While it appears that Clinton will not face a tough primary challenge in 2016, she is aiming to show voters she plans to earn their support and won't take the Democratic Party's nomination for granted, experts said.

The strategy is also aimed at playing to what Clinton allies see as her strengths. Friends and advisers have long said she is more at ease in small group settings and one-on-one conversations where she can display her policy expertise, as well as personal warmth that she sometimes struggles to convey in front of larger crowds.

When Clinton ran for the U.S. Senate in 2000, she kicked off her campaign with a listening tour across New York state.

The approach also comes with risks. More loosely scripted appearances increase the chances that Clinton could be drawn off message or make a misstep that causes a distraction for the campaign, experts say. The former secretary of state has also been off the campaign trail for years, and observers said she seemed rusty in fielding questions during interviews on a book tour last year.

The exact date of Clinton's launch is a closely guarded secret, but the announcement is expected by mid-April. Clinton aides have been checking in with longtime supporters on their whereabouts this month and Democratic operatives in Iowa and New Hampshire have essentially been put on standby.

Clinton may make the official announcement with an online video or social media post, though those plans are still being finalized. She is expected to quickly hit the campaign trail, with stops in Iowa and New Hampshire.

It's unclear whether Clinton's husband, former President Bill Clinton, and her daughter, Chelsea, will appear at solo events in the campaign's early stages.