Analysts think Freeport-McMoRan Copper & Gold's (FCX) $6 bil bid for Plains Exploration & Production (PXP) could go either way at Mon.'s vote. Originally Freeport's cash and stock offer was about $50 per Plains share. But as Freeport's stock slid, the value fell and is now about $46. Proxy advisers suggest Plains shareholders vote no. Freeport has said it won't sweeten the offer. Plains shares closed up 1% at 45.55. Freeport shares climbed 2% to 32.68.