The National Republican Senatorial Committee (NRSC) is reserving between $6 million and $6.5 million worth of North Carolina television time, an NRSC source confirms to The Hill.

The major investment would help boost North Carolina House Speaker Thom TillisThomas (Thom) Roland TillisThe Hill's Morning Report — After contentious week, Trump heads for Japan Collins offering bill to boost battery research as GOP pushes energy 'innovation' Lawmakers call for investigation after census hired registered sex offender MORE (R) against Sen. Kay HaganKay Ruthven HaganNorth Carolina businessman will challenge Tillis in GOP primary Embattled senators fill coffers ahead of 2020 NC state senator meets with DSCC as Dems eye challenge to Tillis MORE (D-N.C.). Tillis has trailed Hagan by a narrow margin in most polls.

"Our internals show that North Carolina is starting to break toward Thom Tillis, and we are prioritizing the North Carolina race, ensuring that Tillis has the resources necessary to defeat Kay Hagan," said NRSC spokeswoman Brook Hougesen. "Democrats have spent $43 million so far in North Carolina and Kay Hagan remains stuck at 44 percent. North Carolinians deserve to know that Tillis is the only candidate in the race with a proven record of getting things done unlike Hagan who has been asleep at the wheel on key national security issues from ISIS to our borders."

Tillis released an internal poll last week that found Hagan leading by 44 to 42 percent.

Republicans have expressed some frustration with Tillis's campaign, especially his weak fundraising, and Hagan has been able to maintain a small lead in the race partly by outspending him on television. But many Republican strategists have said — and this big buy confirms — that they believe if they can even out the air war that Tillis still has a real shot at victory.