(CNN) - With a week to go until Pennsylvania's Democratic primary, all eyes are on Sens. Hillary Clinton and Obama as they continue to battle for their party's nomination.
But, the presidential race had some competition Tuesday when Pope Benedict XVI arrived for his first official visit to the United States, garnering a greeting by President Bush and the first lady when his plane touched down outside of Washington, D.C.
In the latest episdoe of CNN=Politics Daily, Wolf Blitzer provides a quick look at past papal visits. White House Correspondent Ed Henry also reports on the potential impact of the Catholic vote in the 2008 presidential election.
Senior Political Correspondent Candy Crowley reports on how Sen. Clinton is trying to capitalize on the recent 'bitter' gaffe by Sen. Obama and on Obama's counterattack.
Sen. John McCain rolled out his major economic proposals in a speech Tuesday. Dana Bash reports on what the presumptive GOP nominee is doing to lay the groundwork for his face-off with Clinton or Obama during the general election.
Finally, Jessica Yellin takes a look at a potentially critical demographic in the 2008 presidential race - single women.
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