Back in June, I wrote about an article by John Fritze about Chris Van Hollen and Donna Edwards both focusing a significant amount of attention and time on Baltimore, which does not (at the moment) have a candidate in the race.

Five months later, the battle rages on, and Fritze has returned to chart its progress.

Reps. Donna F. Edwards of Prince George’s County and Chris Van Hollen of Montgomery County have appeared more frequently in the Democrat-rich Baltimore region in recent weeks than in any other part of the state — underscoring its battleground status in one of the nation’s most closely watched primary contests.

Both candidates are better known in their own communities on the other side of Route 32, and so Baltimore is wide-open political territory.

“It’s important for Baltimore to enjoy success because that defines success for the entire state,” Edwards, 57, said between campaign stops in the city recently. “I’m spending a lot of time in Baltimore because I’m not from Baltimore, and so I want to learn its neighborhoods and communities — its leaders.”

Van Hollen echoed the sentiment during a recent visit: “My view has always been that the state of Maryland is only going to be strong and vibrant if the city of Baltimore is strong and vibrant.”

While Baltimore’s political influence in the state has diminished with the growth of Montgomery and Prince George’s counties, the region remains fertile ground for Democratic candidates. Together, Baltimore City and Baltimore and Anne Arundel counties accounted for more than a third of the 2012 Democratic primary turnout, about 115,000 voters.

Edwards and Van Hollen are running to succeed retiring Sen. Barbara A. Mikulski, a Highlandtown native and former city councilwoman who has championed the state’s largest city throughout her career. The state’s other senator, Democrat Ben Cardin, grew up in Ashburton.