ALBUQUERQUE , New Mexico ( CNN ) -- Sen. John McCain on Monday defended his opposition to a Democratic bill that would expand education benefits for veterans , saying it would hurt the military that he hopes to lead . Sen. John McCain is co-sponsoring alternative legislation to the GI Bill that the Senate passed last week . The new GI Bill being debated in Congress would expand education benefits for veterans who served at least three years in the military after the September 11 , 2001 , attacks . The bill 's main sponsor , Sen. Jim Webb , is a Virginia Democrat and , like McCain , a Vietnam War veteran . The Senate passed Webb 's bill 75-22 last week . McCain was not in Washington for the vote . Democrats have targeted McCain for his opposition to the Webb legislation . Watch McCain talk about the U.S. debt to veterans . Saying he takes `` a back seat to no one in my affection , respect and devotion to veterans , '' McCain said Webb 's bill would be a disincentive for service members to become noncommissioned officers , which he called `` the backbone of all the services . '' `` In my life , I have learned more from noncommissioned officers I have known and served with than anyone else outside my family , '' McCain said at a Memorial Day event in Albuquerque . `` They are very hard to replace . Encouraging people to choose to not become noncommissioned officers would hurt the military and our country very badly . '' A former Navy officer , McCain was a prisoner of war during Vietnam . McCain , along with Sens . Lindsey Graham of South Carolina and Richard Burr of North Carolina , has introduced an alternative bill that would increase education benefits on a sliding scale based on an individual 's years of service . McCain argues his bill would have a smaller impact on retention rates than the legislation that the Senate passed . `` The office of president , which I am seeking , is a great honor indeed , but it imposes serious responsibilities , '' the presumptive GOP nominee said . `` I can only tell you , I intend to deserve the honor if I am fortunate to receive it , even if it means I must take politically unpopular positions at times and disagree with people for whom I have the highest respect and affection . '' Over the weekend , Sen. Barack Obama , who appears to be the likely Democratic nominee , again tried to tie McCain to Bush by noting that both of them oppose the GI Bill expansion . `` I revere our soldiers and want to make sure they are being treated with honor and respect , '' Obama said Saturday . `` I think the GI Bill is one way for us to do that , and I hope that John McCain and George Bush decide they believe the same thing . '' Sparring between McCain and Obama over the GI Bill got personal last week when McCain said he would not be lectured from someone `` who did not feel it was his responsibility to serve our country in uniform . '' Obama has n't served in the military . Referring to Iraq in his closing comments Monday , McCain said he recognized Americans have grown tired of the war and the mistakes made , `` but we can not react to those mistakes by embracing a course of action that will be an even greater mistake , a mistake of colossal historical proportions . '' `` We must give Gen. [ David ] Petraeus and the Americans he has the honor to command adequate time to salvage from the wreckage of our past mistakes a measure of stability for Iraq and the Middle East , and a more secure future for the American people , '' he said . Later Monday , McCain will attend a fundraiser in Albuquerque . On Tuesday , President Bush will fly to Phoenix , Arizona , for a fundraiser at a private residence . Bush has been one of the Republican Party 's most prolific fundraisers , and McCain will need help to keep up with Democratic fundraising this fall . The McCain campaign said the event will be held at the senator 's home because it is more private . But the Phoenix Business Journal said the event was moved from the Phoenix Convention Center due to lackluster ticket sales and concern over anti-war protesters . A McCain aide denied the report on poor ticket sales . The aide also said the event was n't moved to McCain 's private residence to avoid having the senator and unpopular president appear together on camera . `` We have a policy that fundraising events are closed events , '' the aide said , adding that any confusion about the fundraiser originally being open to the press should be chalked up to the campaign `` working out the kinks '' on its first event with Bush . McCain consistently has trailed the two remaining Democratic presidential candidates in fundraising . The $ 17 million McCain raised in April was dwarfed by the nearly $ 31 million by Obama and the $ 21 million by Sen. Hillary Clinton . McCain also trails both Democrats in the amount of cash on hand . He had nearly $ 22 million in the bank at the end of April , while Obama had more than double that amount -- nearly $ 47 million -- and Clinton had nearly $ 30 million . CNN 's Alexander Marquardt , Ed Henry , Mary Snow and Robert Yoon contributed to this report .
NEW : Sen. John McCain says general must have time to bring stability to Iraq . McCain says GI Bill sponsored by Democrats would hurt military . Score: 6 , Sen. Barack Obama sparring over expanded veterans ' education benefits . President Bush will attend a fundraiser for McCain in Arizona .