The latest Rasmussen Reports election poll of Washington state's Senate race shows Republican Mike McGavick continuing to chip away at the incumbent's lead.

Democratic U.S. Senator Maria Cantwell now leads McGavick 48% to 40%. In March, Cantwell led 49% to 36%.

The new poll is the third in a row in which the incumbent has lost a percentage point of support. And it's the second poll in a row showing her at less than 50% support.

Meanwhile, McGavick, the former Safeco CEO, has made his strongest showing yet, and is firming up support among Republicans (now 86%) and conservatives (79%).

This is the first poll showing McGavick within single digits of Cantwell. In each of the previous five Rasmussen Reports surveys, he had trailed by 13-15 percentage points.

If these trends continue, Cantwell may find herself relying more and more upon Washington state's slight Democratic tilt and the GOP's national problems to hang on to the seat she narrowly won six years ago.

Sixty-two percent (62%) of Washington state voters believe securing the nation's borders and enforcing current law should precede further reform. However, 56% say that the ultimate goal of immigration policy should be to welcome anyone who is not a national security threat, a criminal, or planning to live off the U.S. welfare system. Fifty-one percent (51%) are opposed to forcibly removing all illegal aliens from the United States.

In a March 29 press release, McGavick argues for a combination of greater border security and a guest worker program and giving workers a "path to citizenship." Legislative initiatives promoted on Cantwell's web site pertain mostly to border security and funding for it.

Cantwell is viewed favorably by 58% of voters, unfavorably by 40%. A month ago, those numbers were 60% favorable and 35% unfavorable.

McGavick is viewed favorably by 49%, unfavorably by 33%. That's a big improvement over a month ago when the numbers were 37% favorable and 32% unfavorable.

Most Washington voters, 54%, think tax hikes hurt rather than help the economy, but only a plurality of 46% think tax cuts help the economy. Respondents are divided over which is worse: tax paperwork or going to the dentist.

The rolling average of the last three Rasmussen Reports election polls in Washington shows Cantwell with a 49% to 37% lead. That's the first time she has dipped below 50% in the three poll average.

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