Washington(CNN) The surprisingly close results of Tuesday's special election for a House seat in deep-red Kansas should serve as "a warning sign" to the GOP, Sen. Ted Cruz said Wednesday.
The contest showed the massive shift in the electorate since voters elected Donald Trump President in November. He had carried the Kansas district by 27 percentage points but on Tuesday, Republican Ron Estes only bested Democrat Jim Thompson for the seat previously represented by new CIA Director Mike Pompeo by 7 points.
Though it's far too early to know whether those Democratic gains will hold through the 2018 midterm elections, Kansas was an ominous sign for the GOP ahead of a much closer Georgia 6th District special election next week in Atlanta's northern suburbs -- as well as other upcoming special elections in Montana and South Carolina.
"The radical left is filled with fury right now," Cruz, R-Texas, told radio host Chris Salcedo. "I mean, they're blind with rage. As a result, they're energized -- they will crawl over broken glass. And we knew they would show up, and they did show up."
Cruz, who made a Monday trip to Wichita, told the radio host that he stumped for GOP candidate Ron Estes because "the numbers were looking close" -- and that his party should view the narrow margin as a red flag.
"I think the election was certainly a warning sign," Cruz said.
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There are dangers in reading too much into the Kansas race. Special elections, political operatives say, are like snowflakes -- each taking place in unique circumstances. In Kansas, Republican Gov. Sam Brownback is hugely unpopular. And national Democrats' refusal to spend money helping Thompson meant the race flew under the radar -- which some Democrats argued could have left Republican voters feeling no sense of urgency to turn out to vote.
The Georgia contest will be a much more accurate barometer of the national mood.
For weeks, money has flooded into the northern Atlanta suburbs. Democrat Jon Ossoff has raised $8.3 million -- and the National Republican Congressional Committee and the Congressional Leadership Fund super PAC have spent millions attacking him -- ahead of the 18-person "jungle primary." With a fractured, 11-candidate Republican field, Democrats hope Ossoff can cross the 50% threshold and avoid a June one-on-one runoff with the leading GOP candidate.
The race is also squarely focused on national issues and Trump in particular -- unlike Kansas, where Brownback was also a central factor.
In Kansas, Cruz campaigned alongside Estes, the state treasurer, on Monday, introducing him at a rally and calling on citizens to turn out to vote.
"The danger was that many good conservative Kansans wouldn't pay much attention to the election and wouldn't show up," Cruz said. "I wanted to do everything I could to help turnout."
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To avoid future losses, Republicans must follow through on pledges made to constituents, Cruz said.
"The way to do it is deliver on our promises," Cruz said. "That is what I am urging every day."