Video from Indianapolis TV station WRTV on Monday showed demonstrators crowd into the state capitol building to protest a plan by the Republican-majority legislature to redraw the state’s congressional boundaries.

State senators in Indiana advanced the proposal, although it is not clear if it has the support to become law in a final vote expected later this week even after months of pressure from President Donald Trump.

The legislation was designed to favor GOP candidates in the next year’s midterms. Republicans control the state Senate, but many have been hesitant or openly opposed to the idea of mid-decade redistricting. About a dozen have been threatened over their stance or refusal to immediately declare support over the past several weeks.

Still, the Senate's elections committee voted 6-3 to advance the measure, with one Republican and two Democrats lawmakers opposing it.

The final vote of the whole chamber is expected Thursday and could test Trump's typically iron grip on the Republican Party.

During committee debate Monday night, state Sen. Greg Walker, an Indiana Republican who is against redistricting and voted against it in committee, spoke about threats made against him in recent weeks.

“I refuse to be intimidated,” Walker proclaimed in an impassioned speech during the committee meeting. “I fear for all states if we allow intimidation and threats to become the norm.”

The map, introduced just last Monday and passed by the Republican supermajority in the state House on Friday, would split the city of Indianapolis into four districts distributed across other Republican-leaning areas. It also groups the cities of East Chicago and Gary with a broad rural region.

The contours would eliminate the districts of Indiana's two Democratic congressional representatives: longtime Rep. André Carson of Indianapolis, the state’s only Black member of Congress, and Rep. Frank Mrvan, who represents northwest Indiana near Chicago.

Republicans currently hold seven of the state's nine districts.