(LOS ANGELES TIMES) After a two-week spring recess, Congress returns to work on Tuesday for a make-or-break legislative sprint on two White House priorities – gun violence and immigration reform – in a session that could help define President Obama’s second term.

Spurred by the elementary school shooting last December in Newtown, Conn., tightening the nation’s gun laws was expected to be the top order of business when the Senatereconvenes.

But the gun violence bill could be delayed as negotiators struggle to reach accord on a provision that would require law enforcement background checks for nearly all gun purchases. That element would be the toughest part of a bill that is not expected to include a ban on so-called assault weapons, or limits on high-capacity ammunition magazines.

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