In an election year that many expect to be unkind to Democrats, one of the more interesting legislative races may be brewing in the 21st District of south Snohomish County, which includes Mukilteo, Lynnwood and Edmonds.

Democrat Marko Liias, the incumbent in the race for House Position 2, faces primary challenges from two Republicans and a minor-party candidate who this editorial board endorsed for the seat eight years ago.

One of the GOP challengers, Elizabeth Scott, brings intelligence, a sharply conservative approach and well-considered ideas to the race. The other, Alan Tagle, has a strong private-sector perspective based on his background in banking and as a business owner.

Mike Huisman, a moderate who has run before as a Republican and as a Democrat, has created his own banner this time around — the Senior Side Party. His focus is on issues that affect senior citizens and those who are close to that milestone. He remains an admirably out-of-the-box thinker.

It’s an impressive field — the deepest we’ve seen in years in the 21st.

The top two vote-getters will advance to the Nov. 2 election, and in our view, they should be Liias and Scott. Their distinctive positions in major issues would yield just the kind of debate that’s needed throughout the state.

Liias defends the record forged in Olympia by majority Democrats, pointing to difficult decisions made to balance the budget. He says full funding is key to success in education, and that Democrats have laid the groundwork for it by committing to devoting half the general fund to K-12 when the economy improves.

He has carved out leadership roles in transportation, economic development and job training, areas of obvious importance to the district.

Scott, who has taught English as a foreign language at colleges in the U.S. and abroad, entered the race last year as the Tea Party movement was gaining momentum. Her platform, “Jobs, schools and fiscal responsibility,” no doubt strikes a chord with citizens as she doorbells. She says voters are angry about Olympia’s overspending, and that conservatives like her will address the problem.

Despite their strengths, both Liias and Scott have weaknesses their critics can exploit.

Liias’ primary one is shared by most Democratic incumbents: the budget he speaks so proudly of balancing. (Which, Scott points out, every Legislature is required to do.) Democrats controlled both houses by wide margins, and only managed to balance the budget by getting billions in one-time federal aid, shifting money out of dedicated accounts into the general fund, delaying pension payments and raising some taxes. His way out of a projected $3 billion shortfall in the next biennium includes more tax increases and a hope for job growth, neither of which appear very realistic at this point in time.

Scott has interesting ideas for spending education dollars more efficiently, but not on transportation. Asked where future highway funding will come from as more fuel-efficient cars erode gas tax revenue, she says transit gets too much of the funding pie. But she has no plan for how she would redirect voter-approved transit funding to highways. It’s a major issue, and she needs a much better answer.

These two have plenty to debate. We’d like to hear more from them this fall.