Let me finish tonight with a thought about the challenge facing the Republican Party. That challenge is Sarah Palin. There is no doubt in the world that she leads a powerful political movement in this country or that she carries tremendous clout in terms of picking Republican candidates. When she speaks, she carries weight. If she endorses, it's like a shot of adrenaline in a campaign.But what about Sarah Palin herself. What about her as a candidate for the national office - either president or vice president - or in a major cabinet post like secretary of state or defense? There's the rub. Ask Mitt Romney. Does he think deep down that Sarah Palin has the right stuff to lead this country in a troubling, complicated world? Ask the same of Tim Pawlenty or any of the other serious Republican hopefuls for 2012. Do "they" believe in Sarah Palin's abilities to lead this country in perilous times, to answer that three o'clock in the morning call and make the right decision?Do they buy all this talk of hers that all America needs in this second decade of the 21st century are "common sense conservative solutions?" That a regular person with regular off-the-shelf answers can deal with the tricky, complex questions of economics, science and international relations now before the country?This is the problem for Republicans. The person now leading the party in terms of popular influence can't pass muster with the party's established leaders. How can you win the love of the Tea Partiers if you don't believe in the presidential ability of their hero? Would Sarah Palin make a good president? As long as Romney and Pawlenty and the other would-be Republican nominees pray not to be asked, the party has a problem at its core. And the moment they can speak the phrase "President Sarah Palin" and not have it give them some pause, how long from that moment will their own people still believe in them?