How many hard working Americans would attend?

Let's see, McCain voted against the interests of those earning the minimum wage. 19 times.
Count them out John.

What about the unemployed? Heck, thanks to the Republicans, there are enough unemployed Americans to fill up several stadiums, nevermind just one.  
Not your biggest fans, John.
Men and women who serve in the military? 
When it came time to champion a bill that would make it easier for returning veterans to receive a college education, he wasn't much of a champion. Proved he was a real man, though. Because you have to have a pretty big set of balls to not even show up for the vote.
They probably won't show up for you either, John.

And there's that torture issue. You would think if anyone knows that a prisoner of war is willing to say or confess to anything under the duress of torture, it's McCain. He himself reached a breaking point and finally agreed to sign an anti-American Propaganda confession. Yet he was opposed to a bill that would ban waterboarding. So if America can do it, so can America's enemies. Not sure that comforts any of our men and women on active duty.

That stadium is looking pretty empty, Lieutenant Commander.

Can McCain draw women to Invesco? He opposes a woman’s right to choose.

I don't know any women eager to hear John McCain say "Roe Vs. Wade should be overturned" and have it echo throughout a giant stadium.

What about kids? Kids love big stadiums.

The Children’s Defense Fund rated McCain as the worst senator in Congress for children. He voted against the children’s health care bill last year, then defended Bush’s veto of the bill.

KIds love big stadiums. Kids don't love John McCain.

Senior citizens? Should he ready a hundred buses to pick up the elderly for his stadium debut?

No, they won't come either. Not for someone who thinks of social security as a disgrace.

Gays and lesbians? McCain opposed hate crimes legislation.  
Gays. Lesbians. Not coming.

Environmentalists? Not coming either. John, you scored a "zero" from the League of Conservation Voters last year.
What about Latino Americans? They consistently rate education as a top priority. John McCain consistently voted against funding for Head Start. In fact, he wants to cut funding by more than $968 million.

Not exactly pushing stadium capacity at this point.
It didn't help that he was pleased to have the endorsement of Pastor John Hagee, despite his intolerant comments about Catholics, women, African Americans, Muslims and LGBT Americans. 
Stadium lower level: empty. Stadium upper level: empty.
Wait.
Invesco's corporate box: full.