The pundits keep saying that the Republicans would much rather run against Hillary Clinton and that would be an easier race to win. I think they've got that one exactly wrong. In fact, they should lay off Obama until he secures the Democratic Party's nomination.
Obama is not nearly as adept as Clinton at changing positions with the polls and simply denying that he said what he said. He has staked out some major policy positions that he wont be able to easily wriggle out of. Defeat in Iraq, universal health care, higher taxes and a total of over $800 Billion in new spending may play well to the left during primary season, but the general public isn't going to like it much at all. Americans may not be ecstatic about being in Iraq, but they'd like surrender much less. Nobody wants higher taxes and more government spending and turning over 7% of the nation's economy to government control is not something the public is clamoring for.
The "fairy tale" as Bill Clinton put it, is that the electorate will be satisfied with charisma and charm come November and not pay much attention to policy. Ask McGovern, Mondale and Dukakis if that's really the case.
For now, the GOP should let Obama do his thing and take Hillary out of the game. After that, I think the Democrats, contrary to popular belief at the moment, are going to suffer their biggest general election defeat since Mondale won only one state.