WASHINGTON  Despite an intense effort to distance himself from the way his party has done business in Washington, Senator John McCain is seen by voters as far less likely to bring change to Washington than Senator Barack Obama. He is widely viewed as a “typical Republican” who would continue or expand President Bush’s policies, according to the latest New York Times/CBS News poll.

Polls taken after the Republican convention suggested that Mr. McCain had enjoyed a surge of support  particularly among white women after his selection of Gov. Sarah Palin of Alaska as his running mate  but the latest poll indicates “the Palin effect” was, at least so far, a limited burst of interest. The contest appeared to be roughly where it was before the two conventions and before the vice-presidential selections: Mr. Obama had the support of 48 percent of registered voters, compared with 43 percent for Mr. McCain, a difference within the poll’s margin of sampling error, and statistically unchanged from the tally in the last New York Times/CBS News poll, in mid-August.

The poll showed that Mr. McCain had some enduring strengths, including a substantial advantage over Mr. Obama as a potential commander in chief. It found that for the first time, 50 percent of those surveyed in the Times/CBS News poll said they considered that the troop buildup in Iraq, a policy that Mr. McCain championed from the start, had made things better there.

The poll also underlined the extent to which Mr. McCain’s convention, and his selection of Ms. Palin, had excited Republican base voters about his candidacy, which is no small thing in a contest that continues to be so tight: 47 percent of Mr. McCain’s supporters described themselves as enthused about the Republican Party’s presidential ticket, almost twice what it was before the conventions. As often happens at this time of year, partisans are coalescing around their party’s nominees and independents are increasingly the battleground.