The Gang of Eight immigration reform package easily cleared another procedural hurdle in the Senate on Wednesday and is on track for a final vote by week's end.

As with Monday's procedural vote, there was little suspense over whether senators would get the 60 votes they needed — the bill advanced 66-31 — and a final vote on the potentially historic immigration legislation remains on track for Thursday or Friday.

Two Republicans senators — Roger Wicker of Mississippi and Jeff Chiesa of New Jersey — who voted to advance the bill on Monday flipped, and voted against doing so on Wednesday.

With Wednesday's vote to advance the Gang of Eight package, which was amended to strengthen border security provisions, the clock is officially ticking on the final day and half of debate on the bill.

However, Republican members of the gang were still trying to convince Democratic leaders to allow additional votes on amendments.