COLORADO SPRINGS, Colorado (AFP) - The US presidential race was shaping up as a battle over whether a strong character trumps solid policies Saturday as John McCain attacked his Democratic rival as too weak and Barack Obama worked to refocus voters on the issues. McCain set out on the campaign trail with newly crowned running mate Sarah Palin with a vow to bring reform to Washington and a strong focus on their willingness to buck the party line in order to faithfully serve their country. But a new opinion poll showed American voters remained lukewarm about the youthful Alaska governor, doubting her readiness for major league politics. While six in 10 of those surveyed approved of McCain's selection of Palin, only 42 percent believed Palin had the kind of experience it takes to serve effectively as president if that became necessary, according to the ABC News poll. Meanwhile, Obama's vice presidential pick, US Senator Joseph Biden, passed the experience bar with 66 percent approval, the survey found. On Friday, Obama argued that the presidency was too important to be a "personality contest" and shot back at McCain for failing to focus on the issue which matters most to voters: how they were going to make ends meet in a troubled economy. "I think I've got a pretty good personality," Obama said after ridiculing McCain's campaign manager for saying the election was about personality not issues. "But that's not why I'm running for president. I'm running for president to put people back to work, to give them health care, to make them have college that's affordable." McCain was attempting to co-opt Obama's mantle of change in a year in which polls show Americans overwhelmingly think their country is heading in the wrong direction. McCain mounted sharp attacks dismissing Obama as nothing but talk before delivering an acceptance speech that was long on personal history and short on policy proposals. "This is the ticket to shake up Washington because Senator Obama doesn't have the strength to do it," the decorated war hero told an enthusiastic crowd in Sterling Heights, Michigan Friday night before flying to Colorado for a morning rally. "If you want real change send the ones who have actually done it. Send a team of mavericks who aren't afraid to go to Washington and break some china." Palin, who was elected governor of Alaska two years ago after fighting corruption in her own party, took the attack further and claimed that Barack Obama would not protect the United States if he were to win the November 4 election. She attacked Obama's opposition to sending more troops to Iraq last year and praised McCain's willingness to "put his country first" and support the surge at a time when the war was highly unpopular. "If the United States military had suffered defeat at the hands of Al-Qaeda in Iraq our nation would have been less safe today and millions of innocent would have been left to a violent fate," Palin said. That tragedy would have happened if Barak Obama had gotten his way and Congress had cut off funding for the surge." Obama on Thursday said the surge had "succeeded beyond our wildest dreams" but argued he had shown better judgment than McCain because he opposed the war from the start. He has committed to start troop withdrawals immediately if he is inaugurated president next January, and believes he can get most American soldiers out of Iraq within 16 months. On Friday, he lambasted Republicans for ignoring the impact of the current economic downturn and continued to cast McCain as being in lock-step with unpopular president George W. Bush. "You would think that George Bush and his potential Republican successor John McCain would be spending a lot of time worrying about the economy," Obama told workers in Duryea, Pennsylvania. "But if you watched the Republican National Convention over the last three days, you wouldn't know that we have the highest unemployment rate in five years because they didn't say a thing about what is going on with the middle class." Noting that the Republican leaders had been emphasizing in recent days that the economy was fundamentally sound despite high oil prices, a weak housing market, credit squeeze and inflation pressures, Obama asked, "Now, what's more fundamental than having a job?" US unemployment jumped to a five-year high of 6.1 percent in August as 84,000 jobs were slashed, according to a report released Friday that sparked fresh fears about recession in the world's biggest economy.