As the presidential candidates prepare for Wednesday night’s debate, polls show President Obama averages a 15-point advantage in Washington over Republican rival Mitt Romney. Washington’s open race for governor is much closer. The two candidates in that contest met Tuesday night in Yakima for a fiery third debate. But the polls highlight a reality for Republican Rob McKenna: he’ll have to woo a good number of Obama voters if he’s to become Washington’s first G-O-P governor in nearly 30 years.