JEFFERSON CITY, Mo. — Missouri Sen. Claire McCaskill on Tuesday canceled her campaign events for the remainder of the week in order to spend time with her critically ill mother.

McCaskill's 84-year-old mother, Betty Anne McCaskill, was in an intensive care unit of a St. Louis hospital Tuesday after "becoming critically ill," said McCaskill campaign spokeswoman Caitlin Legacki. The campaign did not disclose any further details about her ailments.

"Claire and her siblings are with her around the clock and ask for both prayers and privacy," Legacki said.

McCaskill on Monday had begun what was supposed to be a several day, get-out-the-vote tour across rural Missouri. But she canceled Tuesday's campaign stops in Mount Vernon, Butler and Clinton. McCaskill also canceled the rest of the tour and all other campaign events through the end of the week, Legacki said.

The Democratic senator is seeking a second term Nov. 6 against Republican Rep. Todd Akin.

Akin campaign adviser Rick Tyler said it was understandable for McCaskill to cancel her events.

"It's sad and we wish her and her mother well, and we send our thoughts and prayers," Tyler said.

McCaskill also missed the Democratic state convention in June to spend time with her ailing mother.

Betty Anne McCaskill has been a frequent presence on her daughter's campaign events over the years and also made her own mark as a political trailblazer when she was the first woman elected to the Columbia City Council.

In 2004, Betty Anne McCaskill helped her daughter's unsuccessful campaign for governor by providing personal testimonies about the rising cost of medical care. She said at the time that her list of medicines had been steadily growing over the years to the point that her costs far exceed her annual prescription drug coverage through private insurance.

During McCaskill's 2006 Senate campaign, her mother traveled around the state with her in an RV. Those sort of events had been limited during this year's campaign. But Betty Anne McCaskill did record a video displayed on McCaskill's campaign website expressing her pride about McCaskill's work trying to straighten out mismanagement of veterans' burial sites at Arlington National Cemetery.

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