Phil Long/AP Photo

NEW PHILADELPHIA, Ohio-Paul Ryan kicked off his two day, eight stop bus tour at a factory here delivering his final argument to this critical state and telling Ohioans they "know the responsibility" and they have a "big decision" in just a week and a half.

"The debate is going to last for about ten more days," Ryan, standing in front of a massive steel copy of the Romney R logo, said. "The choice is yours on November the 6th. Think about November the 7th. Think about how you will feel the next morning when you wake up and turn on the TV. Are we going to have four more years like the last four years? Are we going to wait four more years before we have real change or are we just going to wait ten days?"

The GOP presidential nominee told about 1,000 people inside Gradall Industries, a company that makes highway speed excavators, which he toured beforehand, "We can turn this around."

"We want to wake up that morning and know that we met this moment," Ryan said. "We can do this. The choice is yours…Ohio you know it's you. You know what you have in front of you, you know the responsibility."

Ryan noted that the two campaigns are "closing their arguments" differently, saying "This is a serious election, with serious problems" inferring that is not the final argument his Democratic opponents are sending, adding they have spent "hundreds of millions of dollars of negative ads" in the Buckeye State and "around the other parts of the Midwest to try and disqualify this man," meaning Romney. It's worth noting the Romney campaign has also spent millions in negative advertising in the state. The two campaigns will spend two billion dollars by the time it comes to a close on November 6th, making it the most expensive presidential election in history, by far.

The presidential race has come down to just a few battleground states, but none are more important than Ohio, hence the aggressive air and ground wars by both sides as the race comes to a close.

According to a source tracking presidential campaign ad spending on the TV airwaves, Ohio has been the number one state in ad spending every week since Oct. 8. And - although buys are still being placed - it appears to be the clear winner in the remaining 10 days of the race, above both Florida and Virginia, states that include expensive media markets.

Recent polls have Obama ahead, but still show a major tightening since before the presidential debates. A CNN/ORC poll released last week shows the president with 50 percent and Romney with 46 percent. The latest ABC News/Washington Post national tracking poll released Friday has the race at a dead heat with Romney at 49 percent and Obama at 48 percent.

The president ended a cross-country over night campaign blitz in Cleveland Thursday, while the GOP ticket joined up Friday night for a rally with several thousand Ohioans in North Canton, Ohio. Ryan will make stops in Zanesville, Circleville, Yellow Springs, and Sabina today before making three more stops in the state Sunday, ending with another joint rally with his running mate in Marion, Ohio tomorrow evening.

ABC News' Michael Falcone contributed to this report.