"It's not that Americans don't understand ObamaCare," the former GOP presidential candidate said in a statement. "It's that we understand it all too well."
Texas declined to expand Medicaid under healthcare reform and is relying on the federal government to construct its insurance marketplace.
The state's GOP leaders argue that the Affordable Care Act will drain federal and state budgets while negatively disrupting the healthcare system.
Supporters of the reform note that its provisions will help reduce the burden on Texas hospitals, which provide charity care to the state's uninsured patients.
Sebelius is traveling around the country this summer ahead of the launch of the new insurance exchanges on Oct. 1.