It looks like Palin will be by McCain's side throughout the campaign season. Here's First Read:
The McCain campaign is "very seriously considering" having McCain and Palin campaign together more often than not in the next two months, a senior campaign aide said...
The aide said the two have developed a strong chemistry together and will likely utilize it through joint rallies. He likened it to the chemistry Bill Clinton and Al Gore had in 1992, suggesting it was instinctive.
Of course, this has everything to do with the fact that McCain's solo attempts at campaign rallies aren't going well, and Sarah Palin has essentially become the draw on the GOP ticket. It's an advantage for the Democratic ticket. The fact that Cindy McCain is usually by her husband's side means that, for the GOP, the presidential candidate, the vice-presidential candidate, and the presidential candidate's wife are all in one place on any given day. On the Dem side, those three figures are all fully capable of campaigning unaccompanied.