House Republicans seeking to build a pre-election record for getting tough on illegal immigration plan a new vote Thursday on a border fence proposal that won House approval last December.

The bill calls for building more than 700 miles of double-layered fencing along the nearly 2,000-mile border with Mexico. The House approved the same amount of fencing when it passed its enforcement-focused immigration bill last December.

House leaders see the fence construction as a border security issue that needs immediate attention, said Kevin Madden, spokesman for House Majority Leader John Boehner, R-Ohio. The bill is an "emergency measure" to add fencing and technology on the border, he said.

The Senate approved a broader immigration bill in May that proposed construction of 370 miles of fencing. The Senate also provided $1.8 billion in a defense spending bill to build the fence. The border now has 75 miles of fencing along it.

Politics and voter unrest over immigration have kept the two chambers from negotiating a comprehensive immigration bill sought by President Bush that also would provide an avenue to citizenship for millions of illegal immigrants already in the U.S.

With elections looming, opponents balked at offering what they call amnesty to illegal immigrants. Democrats have used the stalemate on immigration to criticize the GOP as ineffective.

House Republicans were expected to announce additional border security measures Thursday. They were still working on how the bills would be enacted — separately, as a package or included in still pending spending bills for the military and homeland security.