The Senator tells PBS’ Gwen Ifill he has shifted his focus on issues like faith-based initiatives and campaign finance.

But he says they pale compared to McCain’s changes on oil drilling, tax cuts and immigration.

“I think is a pretty hard case to make that somehow I’ve been shifting substantially relative to John McCain.” Read excerpts here or Watch video above.

Also says McCain insists on arguing about “tactics” in Iraq, and says he opposes a major government bailout of Fannie Mae and Freddie Mac.