Could Mary Landrieu Be Vulnerable in 2014?

The question has been brought up because of a recent piece done on the races for Senate seats in 2014.  In the rundown by Roll Call, they say that the race for Mary Landrieu's seat in the Senate is a toss-up.

Among names that have been mentioned as possible challengers on the Republican side are Congressman Bill Cassidy and Congressman Jeff Landry.

What do you think?  Will she be re-elected or will someone new represent the Pelican State?