A crucial element: the mix of Democrats and Republicans who show up this election.
By KARL ROVEIt comes down to numbers. And in the final days of this presidential race, from polling data to early voting, they favor Mitt Romney.
He maintains a small but persistent polling edge. As of yesterday afternoon, there had been 31 national surveys in the previous seven days. Mr. Romney led in 19, President Obama in seven, and five were tied. Mr. Romney averaged 48.4%; Mr. Obama, 47.2%. The GOP challenger was at or above 50% in 10 polls, Mr. Obama in none.
The number that may matter the most is Mr. Obama's 47.2% share. As the incumbent, he's likely to find that number going into Election Day is a percentage point or so below what he gets.
For example, in 2004 President George W. Bush had 49% in the final Gallup likely-voter track; he received 50.7% on Election Day. In 1996, President Clinton was at 48% in the last Gallup; he got 49.2% at the polls. And in 1992, President George H.W. Bush was at 37% in the closing Gallup; he collected 37.5% in the balloting.