SAN FRANCISCO (AP) — The acrimonious presidential campaign eases back into action Monday after a weekend pause for the nation to absorb the shock of a horrific mass shooting at a Colorado movie theater.

The massacre stalled a race for the White House that has become increasingly heated in recent weeks. President Barack Obama, Republican rival Mitt Romney and their advisers are now weighing how soon after the shootings to resume their attacks or whether to temper the tenor of the campaign.

"There's not a playbook for this," said Jen Psaki, Obama's campaign spokeswoman. "Just like everybody, we're taking this day by day."