State Democratic chairman Dwight Pelz called it the "race of the year." The candidates have raised more money combined than almost any other legislative contest in the state — with three liberal groups forming a political action committee to oppose the Republican incumbent and business interests funneling money to ward off the Democratic challenger.

Sen. Luke Esser is fighting for a second term against Rep. Rodney Tom in the 48th District, which covers parts of Bellevue, Kirkland and Redmond, as well as Medina, Clyde Hill, Yarrow Point and Hunts Point. Tom switched from a Republican to a Democrat last spring and declared he was running against his former party colleague.

The race is the centerpiece of a larger effort by Democrats to take back the Eastside suburbs, which have long been Republican territory but are now trending more socially liberal. The Democrats believe they can snatch the seat to add to their three-seat Senate majority.

Esser and other Republicans concede the Eastside has changed but say voters choose candidates on their merits.

With national Republican leaders declining in popularity, "it's not the best time in the world to have an R next to your name," Esser said. But, he added, "We're going to win a very close race."

Tom says the Republicans are in "desperation mode."

"In this race, trust me, there's a difference on every major issue."

Esser and Tom have been debating in interviews and forums over the past few weeks, and four major issues have emerged: values, leadership, transportation and education.

Tom says Esser's conservative views — against abortion, embryonic stem-cell research, gay-rights legislation and a requirement for background checks to buy guns at gun shows — don't fit the district.

Tom, meanwhile, supports all four things and says he is moderate on social issues.

Esser's "values are such that he'd make a great senator in Eastern Washington, not east King County," Tom said.

Esser says voters do support some of his views, such as opposition to gay marriage, and even when they don't, "at least they know where I'm coming from."

According to Esser, Tom has "veered to the left" on issues like gay rights and switched his position on issues like the estate tax, opposing its reinstatement during this year's legislative session but deciding to vote no this fall on Initiative 920, which would repeal the tax.

Esser says he's also risen to leadership positions in Olympia, including his current title as Republican floor leader, while Tom has not. And Esser says he's received awards and endorsements from environmental, labor, public-safety and business groups that show he can work with diverse interests.

"You have to prove that you can work with broad constituencies to get things done," Esser said.

Tom defends his positions, which he says were consistent and fair, and counters that Esser has failed his constituents on their two most important issues: education and transportation.

Tom says he's known as the "education champion" in Olympia. He says school advocates lobbying Esser "see a blank stare in his eyes."

Esser supports the current 60 percent "super-majority" requirement for school levies, while Tom supports a simple majority. Esser also voted against gas-tax increases in 2003 and 2005 that devoted billions of dollars to transportation projects, while Tom voted yes.

"If he was everything in education and transportation he said he was, I'd stay home," Tom said.

Esser says he has worked to improve funding for education, and he said he was one of the key lawmakers who got the regional-transportation package to voters, a plan that will go to the ballot next year.

He says he voted against the gas-tax increases because he has a strict policy of letting voters decide on any tax increase. "I know who the boss is," he said. "The voters are always right."

No matter the outcome of the race, a lot of money will have been spent. Esser has raised about $275,000, and Tom about $220,000, making it among the two or three most expensive legislative races in the state, according to campaign-finance reports.

Ashley Bach: 206-464-2567 or abach@seattletimes.com