Just like when a running back sees an opening, he takes it. And if he's powerful enough -- think Earl Campbell back in his glory days or Chris Berman favorite Mike Alstott or a healthy Ladainian Tomlinson -- he can take that small opening, throw off defenders and cause some damage.
Try as they may, Team McCain doesn't have Earl Campbell's 1978 legs right now. And McCain's offensive line? They're not the Hogs. They best they can do is to look for some mistake, some gaffe, some blunder.
Joe the Senator
Enter Joe Biden.
Yesterday, the Republican camp was trying to score some points from speeches the Delaware Senator gave on Sunday where he guaranteed an international crisis if the Obama-Biden ticket is elected.
"Mark my words: It will not be six months before the world tests Barack Obama like they did John Kennedy," Biden told the crowd. "The world is looking. We're about to elect a brilliant 47-year-old senator president of the United States of America. Watch, we're going to have an international crisis, a generated crisis, to test the mettle of this guy."
“He’s going to have to make some really tough - I don’t know what the decision’s going to be, but I promise you it will occur. As a student of history and having served with seven presidents, I guarantee you it’s going to happen," he said.
The McCain communications team jumped - emailing Biden's remarks around, along with McCain's prepared response and an announcement of a conference call led by Rudy Giuiliani to help frame the issue.
Speaking to a crowd in Belton, Mo., McCain riffed on Biden's remarks, saying that now is not the time for on-the job-training.
"The next President won't have time to get used to the office," McCain said. "We face many challenges here at home, and many enemies abroad in this dangerous world. If Senator Obama is elected, Senator Biden said, we will have an international crisis to test America's new president. We don't want a president who invites testing from the world at a time when our economy is in crisis and Americans are already fighting in two wars."
"What is more troubling is that Senator Biden told their campaign donors that when that crisis hits, they would have to stand with them because it wouldn't be apparent that Senator Obama would have the right response," McCain added.
"Forget apparent," he continued. "Senator Obama won't have the right response, and we know that because we've seen the wrong response from him over and over during this campaign. He opposed the surge strategy that is bringing us victory in Iraq and will bring us victory in Afghanistan."
Much to do about nothing? Yes, according to the Obama-Biden team. Presidents are always tested. Biden was just stating a fact.
"Sen. Biden was making it clear that history has shown presidents face challenges starting on day one, and with our nation fighting two wars and 21st century threats abroad, we know that we need steady leadership in tumultuous times, not the erratic lurching and stubborn ideology of John McCain," said Biden spokesman David Wade.
With two weeks to go, will this stick? Who knows. At this point, you throw anything at the wall. If it doesn't stick, you throw something else.
In the past, however, Team McCain would have had at least a web ad up the morning after calling attention to a perceived gaffe. No ad yet. It's still early.