Democratic senators are bracing for the possibility of high-pressure roll call votes on immigration when the Senate considers a revamped budget reconciliation package this week.

The quirky nature of the reconciliation process — used for budget-only bills that can pass with a simple majority — means the bill that focuses on issues such as climate and health care will be open for amendment on virtually any topic during a lengthy “vote-a-rama” process.

Republicans appear likely to try to force votes on thorny issues such as immigration and border security that could divide Democrats and possibly put the overall bill in jeopardy.

Sen. James Lankford, R-Okla., confirmed Tuesday that Republicans have some immigration-related amendments “in the queue,” though he declined to provide specifics.

And Sen. Lindsey Graham, R-S.C., said he thought border security would come up during the vote-a-rama process. “You can expect a lot of challenging votes,” Graham said.

One major possibility would be an amendment extending public health restrictions known as Title 42, which has been used to expel asylum seekers at the U.S.-Mexico border for more than two years.

The Biden administration’s initial effort in May to end Title 42 expulsions was blocked in court, but the issue divided Democrats who were wary of how it could hurt them politically during a historically high period of migrant border encounters. Several moderate Democrats, including some lawmakers up for reelection in November, pushed the administration to leave the restrictions in place in the weeks before the May 23 rescission date.

In April, Republicans threatened to force a vote on the Title 42 policy when considering a supplemental appropriations bill focused on Ukraine and pandemic aid. The move prompted Democrats to drop billions of dollars in pandemic aid from the package.

Several Senate Democrats — including Sen. Kyrsten Sinema, D-Ariz., who hasn’t said how she’ll vote on the reconciliation bill — joined bipartisan legislation to extend Title 42 restrictions.

Sen. Bob Menendez, D-N.J., warned Democrats against voting for Republican amendments on issues such as immigration that could threaten the overall reconciliation legislation. The surprise announcement of the bill last week marked the latest step in a monthslong effort by Democrats to advance a social spending and tax package.

“Adoption of amendments that would end access to asylum or expand Trump’s border wall will not repair our broken immigration and will put reconciliation at risk,” Menendez tweeted on Monday.

Hundreds of immigrant advocacy groups echoed Menendez’ concerns in a letter released Tuesday. The groups urged senators to reject immigration amendments intended to force Democrats to take difficult votes, including potential amendments to maintain Title 42 restrictions, limit immigrants’ access to health care or ramp up immigration enforcement.

“This bill works to reduce the deficit, fight inflation, invest in both energy and the environment, and lower health care costs for working Americans—Senators should focus on delivering this relief rather than advancing an anti-immigrant agenda,” the groups wrote.

Republican efforts to highlight Democratic weakness on politically tough immigration issues are nothing new. Last August, Republicans won some Democratic support for several immigration-related amendments to the fiscal 2022 budget resolution.

Half the Senate Democratic Conference backed an amendment from Jerry Moran, R-Kan., that suggested “dramatically increasing funding for smart and effective border security measures, improving asylum processing, and reducing immigration court backlogs.” It was agreed to 76-23.

Three Democrats — Catherine Cortez Masto of Nevada, Maggie Hassan of New Hampshire and Mark Kelly of Arizona, all of whom face tough races this fall — voted for an amendment from Bill Hagerty, R-Tenn., to ensure Immigration and Customs Enforcement has “sufficient resources to detain and deport a higher number” of undocumented immigrants who’ve been convicted of a crime.

“I think Republicans will be offering all the amendments that they can think of — as they always do during vote-a-ramas,” New Mexico Democratic Sen. Ben Ray Lujan said. “I’m hoping that we as a caucus will be able to work together to defeat amendments so we can get this reconciliation bill passed.”

Lindsey McPherson contributed to this report.