By Mark Willen, Senior Political Editor June 4, 2008 You couldn't help feeling a little sorry for John McCain last night when the cable networks broke away from his speech to focus on the historic conclusion of the Democratic campaign. But the abrupt departure -- and the far more enthusiastic audiences that greeted Hillary Clinton and Barack Obama -- is indicative of the problems the GOP nominee faces in the months ahead. The speech he gave shows he's well aware of the challenge. McCain's address marked a major shift in approach and signaled his strategy for the fall campaign against Obama. After spending months shoring up the GOP conservative base, McCain moved several steps to the center and sought to cloak himself in Obama's mantel of change. It's a dangerous but probably necessary strategy. McCain was speaking not so much to Republicans last night but to the Democrats and independents awaiting the speeches of Obama and Clinton. He used the opportunity to try to reintroduce himself as the maverick he campaigned as in 2000, separating himself from President Bush and the GOP Congress on Iraq, global warming and federal spending, among other issues. But there are lots of risks in doing that. He can't win without the Republican base and he has to hope that conservatives understand this move to the center is necessary to keep the White House in Republican hands. At the same time, he'll find it difficult to convince Democrats and independents that he's sincere, especially when his policies on the war, taxes, judges and a host of other issues are the same as Bush's. McCain's attempt to steal Obama's theme of change -- he used the word over 30 times last night -- is also a long shot. Everything about Obama's historic campaign represents change, and McCain will have to work hard to persuade voters that a candidate whose very brand is a fresh approach to governing and consensus building is nothing more than another liberal Democrat who happens to be the first African-American nominee of a major party. McCain will have more luck pushing his experience on national security issues and raising questions on Obama's judgment. His speech entwined references to the military, defending American interests and patriotism with jabs at Obama's youth and relative inexperience. Obama, in his remarks, tried to take all three issues head on, making it clear he won't give an inch on his experience or ability. Obama's bow to McCain as a worthy foe was also a warning that the Republican should not underestimate him ("I honor the service of John McCain and I respect his many accomplishments, even if he does not respect mine.") and a promise of an interesting fall campaign.