“The issues aren’t going to go away,” said Senator Mike Rounds of South Dakota, a Republican co-sponsor of the compromise measure. “We’ve still got DACA kids who are going to have to be addressed. We’ve still got a border security system that the president says is a priority.”

With lawmakers anticipating the November elections, when all of the House and one-third of the Senate will be on the ballot, battle lines are likely to harden.

The issue is one that members of both parties can use to motivate their core bases of support. For many conservative Republicans that means taking a hard line on border security and against granting legal status to anyone in the country illegally. For most Democrats, the issue will be erasing the threat of deportation for immigrants brought to the U.S. illegally as children and letting American citizens bring their parents and siblings from abroad.