Are Republicans voting for Clinton in open primaries?

On Tuesday night and Wednesday morning, both MSNBC and CNN commented on the overwhelming white support for Hillary in Mississippi, however, only CNN mentioned that some of Hillary's white support came from Republicans, who may deliberately be voting for her, per Rush Limbaugh's suggestion.

http://politicalticker.blogs.cnn.com/2008/03/11/exit-polls-clinton-draws-republican-support/

Exit polls: Mississippi Democrats divide on racial lines
(CNN) – Mississippi Democratic voters were sharply divided among racial lines in Tuesday's primary, exit polls indicate. As has been the case in many primary states, Obama won overwhelming support from African-American voters. They went for him over Clinton 91-9 percent.

But Mississippi white voters overwhelmingly backed the New York senator, supporting her over Obama 72 percent to 21 percent.

According to the Associated Press, only two other primary states were as racially polarized — neighboring Alabama, and Clinton's former home state of Arkansas.

The exit polls also indicated roughly 30 percent of Mississippi Democratic voters said race was an important factor in their vote, and 60 percent of those voters supported Obama.

– CNN Ticker Producer Alexander Mooney

Exit Polls: Clinton draws Republican support
(CNN) — Are some of Mississippi's Republicans trying to cause mischief? Thirteen percent of the voters in today's Democratic primary identified themselves as Republican; they voted for Clinton, 78 percent to 22 percent. And 37 percent of the Democratic primary voters have a favorable opinion of John McCain; this group also went for Clinton, 62 percent to 37 percent.

Earlier this month, conservative radio host Rush Limbaugh told listeners that since the Republican race was all but over, they should turn out for Clinton, because of his view that she would be a weaker fall opponent for presumptive GOP nominee John McCain — but there is no statistical evidence to indicate his instructions played any role in the Mississippi results.

–CNN's Paul Varian