Republican Gov. Jan Brewer shocked many when she announced in January she wanted to expand Medicaid to 300,000 additional poor Arizonans after opposed Obama’s health care overhaul for years.
Supporters are expected to force the vote by tacking the measure onto a budget bill.
Senate President Andy Biggs is fiercely opposed but has been outmaneuvered by expansion supporters in his Republican caucus. The Senate’s 13 Democrats support the plan and enough of the 17 GOP senators back it that passage appears likely.
The House will likely take up the budget with Medicaid attached next week. Its fate is less sure there as conservatives rally in opposition.