Barack Obama says a vote for John McCain is a vote for George W. Bush’s third term, but a new Rasmussen Reports telephone survey finds that the Democratic hopeful would have a much easier time of it if he were actually running against the incumbent president this year.

At a time when Obama and McCain are locked in a tight race, the poll shows that Obama would rout President Bush 54% to 34%. Looking at the Rasmussen Reports daily Presidential Tracking Poll, McCain is outperforming Bush by more than 15 percentage points.

The poll results also show that Obama would have an easier go of it against two of McCain’s chief rivals for the Republican nomination. The presumptive Democratic nominee leads former Massachusetts Governor Mitt Romney by eight points 49% to 41% and former Arkansas Governor Mike Huckabee 50% to 39%.

However, McCain fares better against Obama than he does against two other prominent Democrats. New York Senator Hillary Clinton leads McCain by eight points, 50% to 42%. Former Vice President Al Gore, the Democratic presidential nominee in 2000, leads McCain 50% to 43%.

These numbers help explain why Election 2008 is competitive even though events so heavily favor the Democrats -- because the Republicans are on course to nominate their strongest possible general election candidate but the Democrats are not. Perhaps even more importantly, the data suggests that voters don’t see a potential McCain Administration as the third term of President Bush.

In all five hypothetical match-ups featured in this article, the Democrat leads the Republican among unaffiliated voters. In the match-up between the two presumptive nominees, McCain holds a slight edge over Obama among those voters.

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