Texas leads the nation in the number of people, a little more than 6 million, with no insurance.
As part of the Affordable Care Act that was implemented 3 years ago, dozens of states are signing up to benefit from expanding Medicaid, but not Texas.
Governor Rick Perry says he rejects the so-called "Obamacare power grab" and will block any measure to expand it.
Texas Catholic cleric Father Kevin Collins is leading 200 religious and community leaders to Austin this week to try to convince state lawmakers:
"It'll help people who can't afford insurance. It'll help our hospital district all across. It'll help by bringing more dollars to the state, so more people will have jobs to help take care of these people."
According to a poll taken by the American Cancer Society, 59 percent of Texans believe Medicaid service should be expanded under the Affordable Care Act.
"The Dallas County Commissioners just passed a resolution, asking the Governor to expand Medicaid. We're hoping our county commissioners will do the same. We know that the health care organizations want it. We certainly know that our hospital district wants it. It's a way that will benefit so many people."
But not everyone agrees with the expansion. This is Linda Edwards Gockel with the Texas Health and Human Services Commission.
"Medicaid is already one-quarter of the state's total budget. Another concern — that Commissioner Janek of the Health and Human Services Commission has discussed — is that we would be putting more money into a system that's already broken, that first we need to find ways for it to operate more efficiently, and have better outcomes for the people that it serves."
Officials say Texas Medicaid expansion would not only generate a hundred billion dollars in federal money for the state, it would also mean nearly a billion dollars in revenue for managed care plans like Amerigroup and WellPoint.
Vivian Ho is a health economist at Rice University.
"Amerigroup and WellPoint have had great experience in other states, taking care of Medicaid patients. So, this has to be a win-win situation for Texans, because what we have are private companies that can come in here and compete, and provide high quality health care to patients that are currently being paid for, in terms of their care, by taxpayers dollars here in the state."
Meanwhile, a Dallas lawmaker has filed a bill to expand Medicaid in accordance with the Affordable Care Act, but Governor Perry must sign it before it becomes law.