Rasmussen Reports: "National Poll: Clinton 35% Obama 33%"

Rasmussen Reports:

For the fourth time in five weeks, a national Rasmussen Reports telephone survey of Likely Democratic Primary Voters shows Senators Hillary Clinton and Barack Obama within two points of each other. This week, it’s Clinton 35% Obama 33%. Former Senator John Edwards is in third place with 14% support. New Mexico Governor Bill Richardson is a distant fourth at 3%.

However, the race may not be as close as those numbers suggest. The Rasmussen Reports sample includes not only Democrats, but also independents who say they are likely to vote in a Democratic Primary. Among Democrats only, Clinton leads by eight percentage points, 39% to 31% (with Edwards at 15%). That’s little changed from a week ago when Clinton led by eleven among Democrats in the survey.

Obama does better when independents are included because he currently holds a two-to-one advantage over Clinton among those potential voters. Both the number and the preferences of independent voters is more volatile than the preferences of core Democratic voters. Some states have open primaries allowing independents to participate, others allow Democrats only. If the current trends were to continue throughout the Primary season, Clinton would handily win the states allowing only Democrats to vote while Obama would be competitive in others.

This puts Clinton in a similar position to John Kerry in 2004 and George W. Bush in 2000. As Kerry swept to the nomination, John Edwards was most competitive in states that allowed independents to participate in their primaries. In Election 2000, Senator John McCain was able to surprise Bush in New Hampshire due to that state’s open Primary and the fact that there was little competition on the Democratic side of the debate. Throughout his challenge, McCain was most competitive in places that allowed independents to participate. However, he was never a serious threat to Bush in states with Republican-only primaries.