Thousands of teachers rallied at the Kentucky Capitol on Friday, urging lawmakers to override Bevin's vetoes.
Erlanger-Elsmere and Gallatin County school districts announced ahead of time Thursday that they are closing so teachers can head to Frankfort and protest pension reform.
Republican Rep. Jeff Hoover told his colleagues not to trust Bevin, reminding them the governor promised to call a special session past year to change the state's struggling pension system but never did.
Observers expect close votes on the overrides.
Bevin vetoed the budget, which spends about $600 million more than his proposed spending plan.
Rep. Phil Moffett, another Jefferson County Republican, posted on Facebook that he is not a fan of the name calling, saying teachers and unions "called us everything from scabs to worthless".
Sen. Morgan McGarvey, a Democrat from Louisville, warned that lawmakers could be giving Bevin license to cut millions of dollars from the budget without their input - or even to call the legislature back for a special session. The demonstrations have been inspired by West Virginia teachers, whose nine-day walkout after many years without raises led to a 5 percent pay hike.More news: CWG 2018: Wrestler Bajrang Punia Wins Gold Medal In Men's 65kg Category
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"By enacting Senate Bill 151, Gov. (Matt) Bevin and the General Assembly have substantially impaired and broken that contract in violation of the Kentucky Constitution and state statute", Beshear said.
In Arizona, after weeks of teacher protests and walkout threats across the state, Gov. Doug Ducey is promising a net 20 percent raise by 2020. Gov. Mary Fallin signed legislation raising teacher salaries by about $6,100 and providing millions in new education funding, but many say schools need more money. But not rejecting the vetoes means the state government won't have money to operate for the next two years. Acting House Speaker David Osborne said there are no new bills, but said lawmakers are considering amendments.
Kentucky teachers haven't asked for a raise.
Attorney General Andy Beshear went to court Wednesday seeking to invalidate a controversial pension reform bill passed by lawmakers without public debate or a financial analysis. They are instead focused on overall funding.
The bill does not change how long current teachers must work before being eligible for full retirement benefits, but future teachers would need to turn 65 years old and have at least five years of service to get full benefits, or would need to be at least 57 years old and have an age and years of service that add up to at least 87.
Kentucky's lawmakers have struggled with the complexities of passing a two-year state budget, searching for education funding and trying to fix one of the country's worst-funded pension systems.
Opponents worry this will discourage young people from becoming teachers.