Perdue's legislation seeks to halve the number of immigrants legally allowed into the U.S. each year, including refugees, and freeze the number of employment-based greencards at 140,000 a year. It would also prioritize would-be migrants who speak English, are well-educated and already have job offers while ending the current preference offered to the extended family of immigrants already living legally in the U.S.
The bill won near-instantaneous rebuke from Democrats. It has also divided some in the GOP, since many businesses rely on immigrants.
Isakson's comments drew cheers and jeers from the crowd at different moments, and some attendees shouted at the Republican for not being direct about whether he would support the bill.
When pressed by reporters after the event, Isakson said the RAISE Act was a "fine piece of legislation" but he ultimately hedged on whether he would vote for the measure in its current form.
"When I get to the point of making that decision I possibly could, but I reserve the right not to," he said. "I’m just not at that point yet."
Read more on myAJC:
Isakson faces frustrated voters at Kennesaw town hall