Former House Speaker Dennis Hastert (R-Ill.) is slated to headline a fundraiser for Rep. Todd Tiahrt's (R-Kan.) Senate campaign, according to an invitation to the event obtained by The Hill.

The fundraiser will occur on Monday, April 20 in Chicago, according the invite. Tickets to the luncheon are $1,000 each.

Tiahrt is running for retiring Sen. Sam Brownback's (R) seat. He is currently locked in what is anticipated to be a close GOP primary against Rep. Jerry MoranGerald (Jerry) MoranOvernight Cybersecurity: Kushner was contacted about WikiLeaks before election | Tech experts blast Trump's 'extreme vetting' plan | Senate passes defense bill with measure to modernize feds' IT Ensuring that defense agencies will have access to a community of entrepreneurs and innovators Provision to modernize federal IT in compromise defense bill MORE.

Interestingly, Hastert's support of Tiahrt coincides with his apparent distaste for Moran. In his 2004 book, "Speaker," Hastert criticized Moran without specifically naming him for saying he would vote one way on legislation than voting another.

Writing about the 2003 vote that passed Medicare prescription drug legislation by five votes, Hastert singled out Moran.

"Some members had assured me that they would be with us, but when the crunch came, they weren't," Hastert wrote. "One prairie state member, a fourth-term representative from a solidly Republican district, voted no, then ran and hid. I sent people to find him. They couldn't. Representative Tom Osborne, a Republican from Nebraska, went to look for him to no avail."

Moran disputed the characterization in the book, telling the Associated Press that the passage