A Democrat running for a congressional seat in an ultra-conservative district is touting support from a Bernie Sanders-aligned group in the final days before a Kansas special election on Tuesday that appears to be unexpectedly close.

There’s been a swell of support for James Thompson, the Democrat running to fill the seat vacated by Tea Party congressman Mike Pompeo, who was tapped by President Donald Trump to lead the CIA. Republicans have stepped up spending in the race, signaling they could be worried about the result.

Along with the Kansas race, Democrats are looking to special elections in Georgia and Montana as early bellwethers of enthusiasm for candidates under President Donald Trump.

As Tuesday approached, Thompson ― running to represent the district that is home to Koch industries ― embraced support from Our Revolution, the progressive group that grew out of Bernie Sanders’ presidential campaign.

So proud to have endorsement of @OurRevolution. @BernieSanders proved PEOPLE power can beat big money. Help us win: https://t.co/gyGma3OeQu — James Thompson (@JamesThompsonKS) April 7, 2017

Early vote numbers aren’t necessarily an indicator of final turnout, but Tom Bonier, CEO of Democratic electoral data strategy firm TargetSmart Communications, noted that the closeness of the race could signal larger problems for Republicans.

1) This KSCD4 special election on Tuesday certainly intrigues. Registered Dems are 7% behind GOPs in the early/absentee vote. pic.twitter.com/VAXAggTTJb — Tom Bonier (@tbonier) April 8, 2017

6) Nevertheless, the fact that we are talking about a special election in a deeply red district speaks to the problems the GOP are facing — Tom Bonier (@tbonier) April 8, 2017

7) If this race is even close, you'll likely see a lot of deeply concerned members of congress, much less likely to embrace Trump's agenda. — Tom Bonier (@tbonier) April 8, 2017

Republicans are injecting well over $100,000 in spending in the final weeks of the race, a portion of which will be spent targeting Thompson.

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