In her party's weekly radio address, Rep. Hilda Solis of California said Bush and Senate Majority Leader Bill Frist, R-Tennesse, "lack real leadership to stop extremists in their party" from thwarting immigration legislation.

Earlier this month, the Senate failed to pass a bill when Frist and Senate Democratic leader Harry Reid could not agree on a procedure for voting on amendments to legislation that would strengthen border security, create a guest-worker program and offer eventual citizenship to many of the estimated 11 million illegal immigrants in the country.

"What America saw during the last few weeks did not happen overnight," said Solis, the daughter of Mexican and Nicaraguan immigrants. "The Republican Party set out to scapegoat immigrants in order to divide voters and win elections long ago, just as they did in the past elections on issues such as gay marriage."