More than 200 people flocked to the Idaho Capitol this morning for a hearing on a bill to void President Obama's health care overhaul.  Dozens at the House State Affairs Committee wore yellow "Yes Nullify" stickers on their shirts or jackets.  Many were tea party adherents; others included small business owners and citizens who fear the 2009 federal law will not only limit their rights, but increase their health insurance costs and expand the power of the Internal Revenue Service.  The measure would forbid Idaho agencies from putting the law into effect - a declaration of state sovereignty over what the bill's advocates call a federal power grab.  Constitutional scholars and the Idaho attorney general have said federal laws trump those of states, so attempts to nullify the law are unlikely to survive legal challenges. They say Idaho is better off pursuing the case in court, where a federal judge in Florida has already ruled against the overhaul even as other courts have ruled more favorably. It's likely bound for U.S. Supreme Court review.