“It’s not surprising that Chuck Schumer is spending tens of millions of dollars to keep Claire McCaskill in the Senate,” Hawley told the Post-Dispatch. “She votes with him nearly 90 percent of the time. When it comes to building a wall, supporting conservative judges and cutting taxes, she is with Chuck Schumer and against Missouri.”

According to the CRP analysis, the National Republican Senatorial Committee has been one of the biggest spenders for Hawley so far, laying down almost $4 million praising him or attacking McCaskill. That committee taps top Republican donors as well as rank-and-file givers to help Republicans get elected to the Senate.

McCaskill has long tried to portray herself as an independent, willing to buck her own leadership, including Schumer, when necessary.

“Certainly he has moments when he is not (bipartisan) and I tell him so,” McCaskill told the Post-Dispatch this summer. “In fact I have told him to be quiet and quit getting his mug all over television, that he is not always helpful.”