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Few in Washington want to see House and Senate negotiators strike a budget deal more than advocates for immigration reform.

Their interest is not so much in the policy as the timing. The unending fiscal battles have repeatedly stolen the spotlight from immigration in the House, and the government shutdown in October sapped the legislative push of both time and political good will.

With Speaker John Boehner (R-Ohio) taking steps to revive immigration reform, advocates now see one remaining window for action in the early part of 2014, before election season begins.

But that opportunity will be lost, lawmakers and aides say, if yet another budget fight erupts in January and February.