Former Texas Solicitor General Ted Cruz (R) has loaned his campaign $400,000 for the stretch run of his Senate primary campaign, according to the Dallas Morning News, a sign that he's worried he needs to spend to ensure he makes the runoff election against Texas Lt. Gov. David Dewhurst (R).

The multimillionaire Dewhurst and a super-PAC backing him have spent more than $10 million on the race, approximately five times more than Cruz and his allies have raised and spent. Cruz, a Tea Party favorite, hopes that if he can force a runoff and get a clear one-on-one shot against Dewhurst he can catch up with him in the second round of voting.

There have been no recent credible public polls, but Dewhurst's internal polls show he's close to the 50 percent mark needed to avoid a runoff, while both Cruz and Dallas Mayor Tom Leppert contend Dewhurst is far below that mark.