Maryland Democratic gubernatorial candidates, Del. Heather R. Mizeur, from left, Attorney General Douglas F. Gansler and Lt. Gov. Anthony G. Brown, after participating in a debate this month. (Photo by Matt McClain/The Washington Post)

With just four weeks remaining until the primaries in Maryland, Tuesday is shaping up as an action-packed day in state politics.

The running mates of the three major Democratic gubernatorial contenders have a televised debate in the morning. Two of the three Democratic candidates for governor will meet in a televised debate in the evening.

And most Maryland hopefuls — including gubernatorial contenders Anthony G. Brown and Douglas F. Gansler — must file campaign finance reports for the first time since January. Those filings will give the public a sense of candidates’ spending muscle heading into the home stretch of the governor’s contest and races for attorney general, state legislative seats and Montgomery county executive, among others.

Here are three things to keep an eye on:

Will Anthony Brown’s debate no-show hurt him?

If everything plays out as advertised, viewers of the Fox affiliate in Baltimore will be treated to a bizarre spectacle Tuesday night: a gubernatorial debate between Gansler and Heather R. Mizeur — and an empty “spot on the stage” representing Brown, the state’s lieutenant governor and the front-runner in the race.

Brown’s camp says he is not participating in the debate out of principle. His, Gansler’s and Mizeur’s campaigns spent weeks negotiating a debate schedule, and agreed to three debates. This one, hosted by WBFF-TV in Baltimore, was not among them.

One of the three that Brown agreed to will be broadcast only on radio. Gansler, the state’s attorney general, and Mizeur, a delegate from Montgomery County, say Brown failed to live up to a pledge to participate in three televised debates. They say they will debate without Brown Tuesday night to live up to their own three-televised-debate commitment.

Brown’s absence carries some risk.

Gansler and Mizeur will get a free hour of exposure in a television market where all three Washington-area candidates are not particularly well known (the debate is supposed to focus on issues of particular importance to the Baltimore area). The larger storyline may turn out to be that Brown ducked the fight — not a notion he would like to see stick.

But since Brown’s absence comes on such a packed political day, the damage could be relatively short-lived. The final two gubernatorial debates — which will include all three major contenders — are next week.

Tuesday night’s debate on Fox45 starts at 8 p.m. and will also be broadcast on NewsChannel 8 in the Washington area and streamed lived on

Will the running mates score any points?

The Democratic lieutenant governor candidates on the tickets of Brown, Gansler and Mizeur will get an hour to make their cases on Tuesday morning.

Howard County Executive Ken Ulman, Del. Jolene Ivey (Prince George’s) and pastor Delman Coates are all scheduled to appear on NewsChannel 8 in a rapid-fire debate hosted at 10 a.m. by Bruce DePuyt that will also be broadcast on radio.

All three running mates have been solid additions to their respective tickets. But it’s hard to envision Tuesday’s debate moving the dial much, as they will be challenged to advance arguments for their principals that haven’t already been made.

Ulman routinely turns in steady performances, which is all that Brown needs from this debate. Ivey has embraced her role as an attack dog — but Gansler has already made plenty of headlines with his own attempts to tear down Brown.

Coates probably has the biggest opportunity to help his ticket, assuming he comes across as knowledgeable on a wide range of issues and can make the case for Mizeur as a viable alternative to Brown and Gansler.

The money chase

Tuesday will be the first time since January that Brown and Gansler have had to disclose their fundraising activity. Back then, Brown’s ticket had nearly $7.1 million in the bank, compared to $6.3 million for Gansler’s ticket. (Mizeur, who is participating in the public financing system, has had to make several disclosures since then.)

The new numbers will reflect momentum in the race in recent months, at least in the eyes of political donors. And there’s also a practical impact: The final weeks of the race will be the most expensive, as TV advertising accelerates and candidates step up efforts to make sure people get to the polls on a primary date that is new to Maryland.

The reports will also provide a sense of how the candidates — both Democrats and the much less well-financed Republicans — have spent their money over the past five months.

And they will help clarify the narrative of several other races heading into the home stretch.

In the Democratic primary for attorney general, for example, a strong finance report could boost the prospects of Sen. Brian E. Frosh (Montgomery), who has the backing of much of the party establishment but has been trailing in the polls against Del. Jon S. Cardin (Baltimore County). The race also includes Del. Aisha N. Braveboy (Prince George’s).

And the public will get a sense of how well positioned the candidates are in several hotly contested primaries for legislative seats, both among Democrats and Republicans.