Home is where the voters are. Home is Rockville in the morning, where Martin O'Malley, mayor of Baltimore, told the TV cameras yesterday that he is who he is "because of the lessons I learned here." Then he scooted away before anyone could ask substantive questions about the county where he hasn't lived since college. In the afternoon, home is Baltimore, where he announced his candidacy for governor of Maryland before a friendly crowd.

Home is a nostalgic notion, a note O'Malley hit repeatedly during his address in a lovely park next to the office of his likely rival in next year's Democratic primary, Montgomery County Executive Doug Duncan. It was here in Rockville, where he grew up, O'Malley said, that "I learned to look and search for the face of God in others, especially in the faces of the homeless men" he saw on his way to Gonzaga College High School in the District. On this day, he could search the supporters assembled for his homecoming and see a Montgomery County that exists only in his memories, a crowd that was 99 percent white in a county that looks like a gathering from most of the globe.

Home is a fungible concept for a politician seeking office. If you weren't paying close attention, you might think that Gov. Bob Ehrlich, who needs a strong showing in the Baltimore area to win a second term, was really a talk show host on WBAL, the Baltimore radio station where he regularly kibitzes on local politics and tells Maryland's story his way, without pesky intrusions by opponents, reporters or facts.

Maryland politicians from the Baltimore area have long acted as if the only home that matters is theirs.

The coming election ("coming" is a bit strong -- Virginians have yet to vote this year), the two largest buckets of Democratic votes will be in Prince George's and Montgomery counties, a good deal more than in Baltimore and its suburbs. Beyond the primary, the D.C. suburbs also will be a more powerful factor than ever before. And 45 percent of Maryland voters now view the state's political news via Washington TV.

Yet state politics remains Baltimore- centric. Duncan's candidacy is widely dismissed simply because he's from Montgomery -- a kiss of death akin to a national campaign based in Massachusetts.

O'Malley appears to be running as the guy from both Baltimore and Montgomery, which should be interesting. Ehrlich seems to be making no such effort. Instead, it looks as if he's signed up with the Peter Angelos jihad against Washington.

We learn this week that it's not just Orioles owner Angelos, but also Bobby Haircut who is responsible for most Nationals games not being on TV this opening season.

In a full-page ad in the Baltimore Sun -- Angelos apparently has given up on his old saw about the Orioles being the Washington area's team, too -- the Orioles show Ehrlich in an O's jacket under a giant "Thank You!" The ad thanks the governor for "his unwavering support of the Orioles during successful negotiations with Major League Baseball to help ensure the long-term financial viability of baseball in Baltimore."

On Tuesday night's Orioles telecast -- maybe the guv didn't realize that O's games are all on Washington TV -- Ehrlich explained: "We were able to lobby, to negotiate under the radar with Major League Baseball to protect this franchise. They needed to know we were very serious about how far we were willing to go to protect this franchise."

Ehrlich was the courier for Angelos's threat to sue baseball if he didn't get the sweetheart TV deal that prevents the Nationals from becoming a major-market player. "This could -- could -- end up in court in relatively short term," the governor said on WBAL in December, at the height of the talks with MLB.

Between tugs by his security detail, O'Malley told me yesterday that he wouldn't have done what Ehrlich did. "My position is 'fair is fair,' " the mayor said. "Most people in Baltimore don't begrudge the Washington area having a baseball team." And off he went to Prince George's for lunch and on home to Baltimore.

O'Malley's press aide tried to sell me on attending the show's Baltimore act: "Nothing major will happen in Rockville; that's just about touching base with where he grew up. The real event is in Baltimore."

But we already knew that.

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