It's the summer-time blues for Obama, McCain

By Steve Holland

WASHINGTON (Reuters) - It is the summer-time blues for both Democrat Barack Obama and Republican John McCain.

Despite a political environment favorable to him, Obama has yet to build a substantial lead over McCain in national opinion polls and lately has been defending himself against charges of making policy shifts to endear himself to centrist voters.

For McCain, his campaign has been unable to take advantage of the opening Obama has given him, causing concern and frustration among some Republicans who already are worried about the party's prospects in the Nov. 4 election.

National opinion polls give Obama a lead with four months to go until Election Day but his advantage is not insurmountable.

A Pew Research Center survey conducted in late June put Obama up over McCain 48 percent to 40 percent, while Gallup's daily tracking poll has Obama ahead 46-43.

This is despite political headwinds that face Republicans: A sagging U.S. economy, $4-a-gallon gasoline and an unpopular Republican President George W. Bush.

Political experts say voters still appear to have some doubts about the 46-year-old Obama, a first-term Illinois senator.

"He still has not crossed the threshold of the voters' comfort level," said Democratic strategist Bud Jackson. On the other hand, said Jackson, "he already has a lead despite the fact that he is less well-known and he has more room to gain than John McCain."