Betting comes naturally to Nevadans, but the stakes are high and the odds are poor for a last-ditch effort to keep 77,000 tons of nuclear waste out of a proposed high-level radioactive waste facility in Yucca Mountain. The state’s U.S. senators are about to unveil a multi-million dollar media blitz aimed at swaying the votes of key Republican lawmakers — largely by showing them the potentially uncomfortable consequences to their job security when constituents find out that the nuclear waste will be shipped through their states en route to Nevada. The senators are throwing their weight behind a state-funded campaign to spend up to $10 million to air anti-Yucca television and radio ads, especially in New England states. Some Nevada lawmakers, however, are skeptical that the ads will be enough to stop the Yucca juggernaut.