FLINT, MI -- Democratic presidential candidate Hillary Clinton released an ad Wednesday focusing on the Flint water crisis.

"I will fight for you in Flint no matter how long it takes," she says in a speech she made while visiting Flint.

The city is suffering from an ongoing water crisis, which emerged when the city switched water sources and pumped more corrosive water through its aging infrastructure. The water leached lead from the pipes, exposing an unknown number of children in the city to the toxin. Flint residents still can't drink the water and are relying on bottled water and filters.

The Clinton ad also features Pastor Allen Overton, Flint resident Angelina Harris and Flint Mayor Karen Weaver, who has endorsed Clinton in her presidential run.

"She's the one who brought it to another level of attention, and that's what we needed," says Weaver in the ad.

The 60-second ad is titled "This City Means Something" and is airing in Michigan, according to her campaign.

Clinton has purchased $398,000 worth of ads in the state while Democratic contender Bernie Sanders has purchased ads worth $444,130, according to an MLive analysis of political records filed by Michigan television stations.

Clinton visited Flint earlier this month, while Sanders has a planned visit this week. The two -- along with five remaining candidates on the Republican side -- go head to head in a primary on March 8.

Emily Lawler is a Capitol reporter on MLive's statewide Impact Team. You can reach her at elawler@mlive.com, subscribe to her on Facebook or follow her on Twitter: @emilyjanelawler.