Several high-profile Republicans are encouraging Missouri Attorney General Josh Hawley to run for the U.S. Senate next year.

The supporters released a public letter Monday as a means of building support for him to take on Democratic Sen. Claire McCaskill. Some of the signers include former Sen. John Danforth, former Lt. Gov. Peter Kinder and prominent donor David Humphreys.

Hawley has been in office just three months. He said in a statement to The Associated Press that "it is far too early to be thinking about any future election."

U.S. Rep. Ann Wagner is among other Republicans considering a Senate campaign.

Danforth was involved in a similar public letter campaign urging former State Auditor Tom Schweich to run for a 2012 Senate seat and the 2016 governor's race.