Which Candidate’s Narrative Will Prevail?

… Republican Mitt Romney’s campaign argues that it has momentum at the end, and that momentum is decisive in a close race such as this one. …

Democrat Barack Obama’s campaign maintains that the power of the president’s coalition is undiminished, its underlying strength not fully reflected in polls using traditional formulas to forecast which voters will turn out. …

To weigh the strength of those arguments, it’s illustrative to compare the movement in battleground-state polling over the last month, a trend that favors Mr. Romney, with the rising power of the Hispanic and African-American vote over time, and the consistent turnout pattern among young voters, trends that favor Mr. Obama. [cont.]

Gerald Seib, Wall Street Journal