FILE - In this Sept. 3, 2008 file photo, Republican vice presidential candidate Sarah Palin, left, is joined by Republican presidential candidate John McCain, right, and daughter Piper at the end of her speech at the Republican National Convention in St. Paul, Minn. Alaska Gov. Sarah Palin abruptly announced Friday, July 3, 2009 she is resigning from office at the end of the month, a shocking move that rattled the Republican party but left open the possibility she would seek a run for the White House in 2012. (AP Photo/Charlie Neibergall)

In this Wednesday, June 17, 2009 file photo, Sen. John McCain, R-Ariz., speaks on Capitol Hill in Washington. President Barack Obama sought to rally support for his domestic initiatives, while Sen. John McCain called for Americans to support Iranian election protesters. The one-time presidential rivals both cited the spirit of the nation's founders in their Fourth of July radio and Internet addresses. (AP Photo/Charles Dharapak, File)

Sen. John McCain, R-Ariz., looks on at right as President Barack Obama meets with members of Congress to discuss immigration, Thursday, June 25, 2009, in the State Dinning Room of the White House in Washington. (AP Photo/Haraz N. Ghanbari)

Senate Health, Education, Labor and Pensions Committee member Sen. John McCain, R-Ariz. asks when lawmakers would have legitimate cost estimates on the health care reform bill as he gestures over a stack of documents comprising of the bill and its amendments, Wednesday, June 17, 2009, during the committee's markup hearing on Capitol Hill in Washington. (AP Photo/Charles Dharapak)

In this photograph provided by CBS, Sen. John McCain, R-Ariz., is interviewed on the CBS talk show "Face the Nation" Sunday, June 21, 2009, in Washington. McCain says the U.S. should board a North Korean ship it is tracking if hard evidence shows it is carrying missiles or other cargo in violation of U.N. resolutions. (AP Photo/CBS Face the Nation, Karin Cooper)

Senate Health, Education, Labor and Pensions Committee member Sen. John McCain, R-Ariz. asks when lawmakers would have legitimate cost estimates on the health care reform bill as he gestures over a stack of documents comprising of the bill and its amendments, Wednesday, June 17, 2009, during the committee's markup hearing on Capitol Hill in Washington. (AP Photo/Charles Dharapak)

Senate Health, Education, Labor and Pensions Committee member Sen. John McCain, R-Ariz. asks when lawmakers would have legitimate cost estimates on the health care reform bill as he gestures over a stack of documents comprising of the bill and its amendments, Wednesday, June 17, 2009, during the committee's markup hearing on Capitol Hill in Washington. (AP Photo/Charles Dharapak)

Senate Health, Education, Labor and Pensions Committee member Sen. John McCain, R-Ariz. asks when lawmakers would have legitimate cost estimates on the health care reform bill as he gestures over a stack of documents comprising of the bill and its amendments, Wednesday, June 17, 2009, during the committee's markup hearing on Capitol Hill in Washington. (AP Photo/Charles Dharapak)

FILE - In this Nov. 4, 2009 file photo, then-Republican presidential candidate Sen. John McCain, R-Ariz., and his wife Cindy, walk back to their car after casting their ballots in the 2008 presidential election in Phoenix, Ariz. (AP Photo/Stephan Savoia, File)

Sen. John McCain, R-Ariz., and his wife Cindy, whose son Jack is graduating, listens as President Barack Obama speaks at the United States Naval Academy graduation ceremony in Annapolis, Md., Friday, May 22, 2009. (AP Photo/Charles Dharapak)