Maryland’s Democratic Gov. Martin O’Malley scored a nearly complete victory over his Virginia counterpart, Republican Bob McDonnell, in Tuesday’s election. (Patrick Semansky/AP)

In their civil but pointed rivalry for cross-Potomac bragging rights, Maryland Democratic Gov. Martin O’Malley scored a nearly complete victory over his Virginia counterpart, Republican Bob McDonnell, in Tuesday’s election.

O’Malley led his party to triumphs on four statewide ballot questions. He also used a new, gerrymandered electoral map to swipe a U.S. congressional seat from the GOP.

On two of the ballot questions, O’Malley helped win advances for Latinos and gay and lesbian voters. Both are important Democratic constituencies whose support should prove quite useful for an ambitious politician eyeing national office.

“If I’m Martin O’Malley, I’m online right now looking at good prices on campaign buses. He had a night I don’t think he could have imagined that sets him up beautifully for a primary contest in four years,” said Todd Eberly, a political scientist at St. Mary’s College.

McDonnell failed to deliver Virginia, a critical national battleground state, for either Republican presidential nominee Mitt Romney or U.S. Senate candidate George Allen.

That abruptly ended a three-year winning streak for McDonnell in campaigns in the Old Dominion in off-year elections.

“There were a number of Republican governors who were not able to bring in their state in the presidential year, and McDonnell is prominent among them,” said Richmond-based political commentator Bob Holsworth.

Romney’s overall loss to President Obama also marked a setback for McDonnell’s national ambitions. He had harbored hopes of being appointed to Romney’s Cabinet, ideally as attorney general.

Instead, the Virginian will have to listen politely while O’Malley boasts about the Democrats’ successes when the two of them appear — as they often do — as antagonists on national television political talk shows.

McDonnell and O’Malley have become informal adversaries partly because their states are neighbors. Also, each man heads his party’s national governors association.

The latter role provided one bright spot for McDonnell on Tuesday. The GOP wrested away a governorship in North Carolina. Another was still up for grabs in Washington state.

However, the Republicans had hoped to do considerably better in gubernatorial races.

McDonnell hardly bears all the responsibility for the GOP’s disappointments in Virginia. As I wrote in a column in early October, Romney’s weaknesses as a candidate threatened to drag down both Allen and McDonnell.

Still, McDonnell had made a strong personal commitment to the Republican presidential and Senate candidates. He endorsed both in the GOP primaries. He put his political organization to work for them.

Moreover, Tuesday’s results suggest that McDonnell hasn’t done enough to nudge the Virginia GOP toward the political center. That’s partly because he is conservative and partly because his room to maneuver is limited by even more conservative Republicans in the General Assembly.

In any case, the party’s profile is hurting its prospects in presidential years when turnout jumps among minorities and young people.

Across the river, meanwhile, O’Malley is positioning himself to appeal to just those growing groups.

He won big for Latinos by advocating successfully for the ballot measure known as the Dream Act. It allows undocumented immigrants to pay in-state tuition at Maryland universities.

He won big for gays and lesbians — and boosted his appeal to the younger generation — with a historic popular vote endorsing same-sex marriage.

“I think the results yesterday show that O’Malley can do very well in the coalition of the ascendant,” Eberly said, using a term popular with the Obama campaign that describes a political alliance among expanding demographic segments.

O’Malley has been on the defensive at times in comparisons with McDonnell because Virginia has a lower unemployment rate than Maryland. On Tuesday, however, the Democrat came out on top on the most important day of the four-year political cycle.

Not too shabby

I got six out of seven correct in my forecasts in Sunday’s column for key election results in the Washington region.

My calls were right on the Democrats’ two big victories in Virginia, the D.C. Council race, and approval in Maryland of same-sex marriage, the Dream Act and that odious congressional redistricting map.

I was wrong to predict that casino gambling would fail in the Free State.

Much of the credit goes to The Washington Post’s ace pollster, Jon Cohen, and his team. To a large extent, I simply trusted their surveys.

I discuss local issues at 8:50 a.m. Friday on WAMU (88.5 FM). For previous columns, go to