Eight Democrats are vying for the 3rd District seat that is being vacated by Cardin.
The field combines newcomers and big names, including longtime TV reporter Andy Barth, former Baltimore Health Commissioner Peter L. Beilenson, second-time candidate Oz Bengur, state Sen. Paula C. Hollinger and former government official Kevin O'Keeffe. Perhaps the biggest name of all belongs to John P. Sarbanes, an attorney who is the son of the retiring senator.
The attorney general race pits Montgomery County State's Attorney Douglas F. Gansler against Stuart O. Simms, a former Baltimore state's attorney and former state Cabinet official.
Gansler, known as aggressive and outspoken, has a solid fundraising lead and has been laying the groundwork for a campaign for years. Simms, who is known as quiet and deliberative, has endorsement from some of the big names in the Democratic establishment. Montgomery County Councilman Thomas E. Perez was declared ineligible late in the race, but his name will appear on the ballot.
The winner will face Frederick County State's Attorney Scott L. Rolle, who has not had much fundraising success but who has the strong backing of Ehrlich.
The Republican who nearly beat Owens for Anne Arundel County executive in 2002 is trying for the office again, but former Del. Phillip D. Bissett faces two state delegates, David G. Boschert and John R. Leopold, along with two educators, assistant schools superintendent Gregory V. Nourse and teacher Tom Angelis.
State Sen. Ralph M. Hughes' retirement has led to a tough race in his Baltimore district.
Six Democrats are running, including Del. Salima S. Marriott, city House delegation chairwoman; Del. Catherine E. Pugh, a former city councilwoman; and Lawrence A. Bell III, former city councilman and mayoral candidate.
What initially looked like an easy ascendency for Del. Bobby A. Zirkin to Hollinger's Senate seat in the Pikesville-Owings Mills area of Baltimore County has turned into a rough-and-tumble primary.
Zirkin and physician Scott Rifkin (the brother of one of Annapolis' most prominent lobbyists) have exchanged attacks for weeks.
Zirkin's move to the Senate race also has led to a free-for-all in the delegates race, with 11 challengers joining incumbent Dels. Dan K. Morhaim and Jon S. Cardin on the primary ballot.
Today is primary day, when registered Democrats and Republicans select nominees. Maryland has a closed primary, so unaffiliated voters are excluded from partisan races.
Polls are open from 7 a.m. to 8 p.m. To find your polling place, go to www.elections. state.md.us/citizens/county_ boards.html.