Well, they're both pretty good singers - though I reckon Jenny from the Block is better than Tony from Number Ten.
But another similarity is they've both appeared on MTV.
Tony Blair was on last week, facing young people's questions on the war in Iraq.
One of my mates in Westminster was asking the people at MTV how it went.
"Do you reckon you'll be able to cope with such an important guest?" he asked.
"Of course we will," said the MTV person. "After all, we had J Lo on last week y'know!!!!"