The Democratic field to replace retiring state Sen. Mary Margaret Whipple (D-Arlington) is shaping up: Del. Bob Brink (D) is out, Arlington County Board member Barbara Favola is in. Del. Patrick Hope (D) is...interested in your opinion about whether he should run.

And blogger, political operative and provocateur Ben Tribbett isn’t ruling out a run either--though, true to form, he’s criticizing Senate Majority Leader Dick Saslaw (D) along the way for a possible plan to redraw Whipple’s seat in redistricting next month so that it would include new precincts in McLean and Great Falls.

Whipple announced last month that she does not plan to run for reelection to her seat, opening up opportunities for Democrats interested in replacing her in a currently heavily Democratic district that includes much of Arlington, and part of Falls Church and Fairfax.

Redistricting could throw a wrench into the plans of anyone interested in the seat. No one knows exactly what the boundaries of state senate districts will be after the General Assembly finishes redrawing maps next month in response to the 2010 census.

In a statement Tuesday, Brink said that he’d been “gratified” that people had encouraged him to run to replace Whipple but has decided he can “best serve Arlingtonians by remaining in the House of Delegates.”

Noting a “tough year” for Arlington in Richmond--and alluding to the “hostile reception” received to a measure to allow Arlington to continue to levy a 5.25 percent hotel occupancy tax, he said the county’s delegation will need to be strong and united next year.

Barbara Favola plans an April announcement of her candidacy but has said she plans to run for the seat. Meanwhile, Del. Patrick Hope (D), in his first term in the House, last week distributed a video in which he asked residents to offer him advice on whether he should run.

“I want to hear you from what’s on your mind and whether you think that I’m the right person to run for her seat,” he says.

Tribbett, meanwhile, who lives in Rosslyn, has been alluding to a possible senate run over Twitter in recent weeks. In an e-mailed statement, he confirmed he is considering seeking the seat but said it would be exceedingly difficult to win if senate Democrats choose to push the district borders westward into Great Falls and McLean.

Doing so, he says, would dilute the voting power of young professionals who live along the Orange line metro corridor in Rosslyn, Courthouse and Ballston.

“I’m outraged by the plans of Senator Saslaw to dilute the youth voter influence in the 31st district by running the district through McLean and Great Falls,” Tribbett wrote. “ The 31st Senate district has the highest concentration of young professionals of any district in Virginia and that influence would be ripped apart by the current Senate redistricting plan that Saslaw is floating.”

He added: “I won’t rule out any campaign yet, but there is no question it would be much more difficult to run in a district that was gerrymandered in such a way.”

In an interview, Whipple said the senate majority’s redistricting proposal is still a work in progress--it’s likely to be unveiled shortly before the General Assembly returns to Richmond April 4.

But she did not deny that leading senate Democrats may propose that expanding her extremely Democratic district into more politically mixed McLean and Great Falls. That scenario could allow Democrats to strengthen other senate districts nearby, including Sen. Janet Howell (D-Fairfax) who currently represents those districts.

“I think there are going to be a number of changes in Northern Virginia and people really are going to have to wait and see how the districts shape up,” Whipple said. But, she added, “It’s advantageous to us, obviously, to make some of our very Democratic districts somewhat less Democratic. And there are so many ways to do that.”

She said she did not believe young professionals who live on the Orange line corridor would find their voting power impacted through such a plan, however.

“That would not be currently the dominant factor in this district,” she said. “So I’m not seeing how they would be diluted.”

Meanwhile, here’s Hope’s video, asking for your advice on a possible senate run: