This poll shows the slimmest margin between Rudy and McCain of any polling outfit in quite some time:

Pew Research Center GOP & Dem National Primary Poll, conducted March 21st-25th, 2007:

Republicans (First Choice – Second Choice)

• Rudy Giuliani 28% – 15%
• John McCain 25% – 15%
• Newt Gingrich 5% – 6%
• Mitt Romney 5% – 5%
• Tommy Thompson 2% – 3%
• Jim Gilmore 2% – *
• Mike Huckabee 1% – 2%
• Duncan Hunter 1% – 15
• Sam Brownback 1% – 1%

Democrats (First Choice – Second Choice)

• Hillary Clinton 24% – 16%
• Barack Obama 23% – 15%
• John Edwards 16% – 13%
• Al Gore 10% – 13%
• Bill Richardson 3% – 3%
• Joe Biden 2% – 2%
• Chris Dodd 1% – 1%
• Dennis Kucinich * – 1%

The margin between Hillary and Obama is worth noting as well…