Story highlights Pollster to Republicans: "Raise money. Do opposition research. Test messages. Target key groups. Start early."

Washington (CNN) One Republican pollster has figured out the only way his party can win next fall: Destroy every Democratic candidate in sight.

In a memo, obtained by CNN's Chris Cillizza , pollster Glen Bolger outlines nine ways Republicans can strengthen their odds of winning in 2018 -- and it is seemingly not going to be easy.

"Make no mistake about it. Tuesday (Election Day) was not just a bad night for Republicans in Virginia," Bolger writes. "The GOP lost three state legislative seats in Georgia special elections held in wealthy suburban districts, two seats on the Delaware County Council in suburban Philadelphia, the Westchester and Nassau County Executive races in New York, and a state senate special election in Washington state that tipped the balance in that chamber back to the Democrats, as well as other races around the country."

As Cillizza has previously pointed out, Republicans may be in deep trouble in 2018 . And Bolger's memo makes no doubts about the difficult environment for Republicans. He writes:

"Do not sit on a lead. Elections are rife with incumbents who polled, saw a big early lead, and throttled down in the campaign, only to be upset. Just because a challenger has little name ID now does not mean a big lead will hold. This is no cycle to rest on your incumbency."

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