Culled an long article with lots of interesting history are Rollcall's key points points on Cardin vs. Mfume vs. Van Hollen:
http://www.rollcall.com/issues/50_106/politics/9032-1.html"With 39 years of elective office under his belt, he’s (Cardin) well-known across the state and is highly respected both at home and in Washington, D.C. His deliberative, cerebral style and passion for policy receives favorable comparisons to Sarbanes, who has held the Senate seat since 1977."
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"Along with these advantages, Cardin appears to enjoy broad, if muted, support from the Maryland Democratic establishment. And as the only Jewish candidate in the race, he is poised to reap political cash from some of the party’s most active national donors."
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"But in assessing what is shaping up to be a highly competitive Democratic primary, there is another part of Cardin’s history to also consider: For all his strengths, which will carry him far in the primary, the 61-year-old Congressman has never once competed in a close election."
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"By contrast, Cardin’s two likeliest Democratic primary opponents, former Rep. Kweisi Mfume, who has already entered the race, and Rep. Chris Van Hollen, who has created an exploratory committee, have plenty of tough political contests under their belts."
And in the race to succeed Cardin in Congress:
http://www.rollcall.com/issues/50_106/atr/9031-1.html"With Rep. Benjamin Cardin (D) now officially running for Senate, add Baltimore City Health Commissioner Peter Beilenson (D) to the list of possible candidates for Cardin’s 3rd district seat."
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"Beilenson, who has been associated with several liberal causes in Maryland through the years, said he would decide on whether to make the House race within the next two months."