The 'Convention Bounce' - What Is It? Does It Determine Who Wins?

Is it all about "the bounce?"

Of course we are referring to the post-convention bounce in the polls typically seen immediately after the convention closes. Do political parties and presidential candidates really benefit from three days of speeches and rallies? The Republicans should know the answer to that question a week from today, and the Democrats will find out on September 9th -- the Sunday after they wrap up in Charlotte.

One the eve of the GOP National convention in Tampa, many in the news media are speculating about the size of the "bounce" in Mitt Romney's poll numbers after he is officially nominated by the Republicans, accepts that nomination, and delivers his speech to close the convention on Thursday night.

Of course there are statistics to support just about any theory you might want to offer on behalf of either candidate, no matter how big or how small their bounce.

Gerhard Peters and John Wolley of the American Presidency Project studied the last 12 presidential conventions, each candidate's bounce, and the results of the November elections.

From 1964 to 2008:

Six of the bounce winners went on win the White House

Five of the bounce winners LOST the election.

And in closest presidential election in American history, the 2000 Bush and Gore tied -- both men generated an 8% post convention bounce in the polls.

Fox News spoke with research guru Larry Sabato, the director of the University of Virginia's Center for Politics, about post-convention bounces. Sabato thinks the fact that Romney and Ryan are relative unknowns compared to President Obama has the potential to create a bigger than normal bounce for the GOP. However, the three major broadcast networks are significantly cutting back their coverage of both the Democrats and Republicans.

Will these "three-day informercials" prove to be winners for both Romney and Obama? Or will one candidate see a huge spike like Bill Clinton's 16% jump in 1992. Or could someone have a "John Kerry" negative bounce? We'll know for certain next Sunday for Romney and the following week for Obama.

Stay tuned.