Three days. Nine states — give or take. A magic 270 electoral votes. For President Barack Obama and rival Mitt Romney, the final touch-and-go stretch of campaigning is down to the numbers.

Mitt Romney speaks as his running mate Rep. Paul Ryan (R-WI) (R) and wife Ann Romney (L) look on during a campaign rally at The Square at Union Centre in West Chester, Ohio (Justin Sullivan/Getty Images)

New hiring reports or a new jobless rate. Spending totals or early vote totals. Percentage points and rhetorical points. Frequency of stops or size of crowds.

In a game of metrics, each camp is looking for that last measure that will separate them at the finish line.

Obama's team is planning a series of larger-than-usual events this weekend aimed at drawing big crowds in battleground states including Ohio, Wisconsin and Virginia.

Romney is set to attend a Saturday morning rally in New Hampshire before making an afternoon appearance in Iowa, and two more appearances in Colorado that evening.

Obama banks on Bill Clinton to clinch close states

Linda Pennywell, a supporter and volunteer for U.S. President Barack Obama, attends a campaign rally at the Franklin County fairgrounds in Ohio (Chip Somodevilla/Getty Images)

In Bill Clinton, Obama has a surrogate that Republican Mitt Romney cannot match.

The former president is sprinting through battleground states and delivering more speeches than Obama himself. He may carry much of the president's re-election hopes on his 66-year-old shoulders.

Clinton and Obama once had a chilly relationship. But now Clinton is working day and night to pick apart Romney's proposals in the folksy yet detailed style he unleashed at the Democratic convention.

At five events Friday in Florida, Clinton said Obama's ideas are superior for health care, the economy and America's future in the global economy.

He will join Obama for a rally Saturday in Virginia and for an event Sunday morning in Concord, N.H. Clinton then will make four stops on Monday in Pennsylvania.

(Copyright 2012 by The Associated Press. All Rights Reserved.)