National Republican Senatorial Committee Chairman John Cornyn (Texas) on Tuesday dodged a pledge to financially support Delaware conservative Christine O'Donnell if she win's Tuesday's Senate primary against Rep. Mike Castle (R-Del.).

Asked if the NRSC would financially back O'Donnell in the general election if she defeats Castle, a popular centrist, in Tuesday's primary, Cornyn said he wouldn't answer until the results are in.

"I am not going to answer that question because it's a hypothetical," Cornyn said with a smile. "I'll talk to you about it tomorrow."

O'Donnell has the backing of some Tea Party leaders as well as former Alaska Gov. Sarah Palin (R) and Sen. Jim DeMint (R-S.C.), but critics say she would be a weaker candidate than Castle against Newcastle County Executive Chris Coons, the expected Democratic nominee, in November.