PRINCETON, NJ -- Barack Obama leads Hillary Clinton by seven percentage points, 49% to 42% in the Gallup Poll Daily tracking three-day average for Feb. 15-17.

The daily tracking at this point is a measure of the sentiments of all Democrats nationally, whether they have had the opportunity to vote in their state's primary or caucus. Obama's seven-point lead in the Feb. 15-17 results suggests that Democrats today, by a slim margin, prefer that he be their party's standard-bearer to Clinton. The next major event that could have an impact on the opinions of Democrats nationally is the Wisconsin primary on Tuesday, Feb. 19.

National Republican preferences for John McCain and Mike Huckabee remain fairly constant, with McCain leading in the Feb. 15-17 three-day average by 28 points, 54% to 26%.

Huckabee did slightly less well in interviewing on Feb. 17, but it is too soon to know if this represents a significant trend. One key focus on the GOP side is the degree to which Huckabee supporters will stand by their man, given the recognition that McCain essentially has the Republican nomination sewn up. On Monday, former president George H.W. Bush endorsed McCain. -- Frank Newport

: Gallup is interviewing 1,000 U.S. adults nationwide each day during 2008. The results reported here are based on combined data from Feb. 15-17, 2008, including interviews with 1,003 Republican and Republican-leaning voters, and 1,201 Democratic and Democratic-leaning voters. For results based on these samples, the maximum margin of sampling error is ±3 percentage points. In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls.