Rand Paul's licking his wounds from a defeat in the North Carolina Senate GOP primary.
On Tuesday, it's Ted Cruz's political muscle that will be put to the test.
The freshman GOP senator from Texas has thrown his support behind a pair of candidates, respectively, in the Nebraska Senate and gubernatorial primary contests, and by Friday he will have made public appearances on behalf of both.
Cruz was the first potential 2016 contender to get behind Ben Sasse, a university president and former congressional chief of staff who has captured the tea party zeitgeist in the Cornhusker State. Sasse has even been dubbed by Slate's Dave Weigel "The Next, Next, Next, Next Ted Cruz." He's in a tight three-way contest with former state treasurer Shane Osborn and Sid Disdale, a wealthy bank executive dropping personal money into the race in its closing week.
Like Paul – the GOP senator from Kentucky – did for Tar Heel state-tea partyer Greg Brannon, Cruz held a rally for Sasse in late April.
"I'm here supporting Ben Sasse because I believe he has the courage to look in the eyes of the party bosses in Washington and say, 'I don't work for you, I work for the people of Nebraska,''' Cruz said in a message very similar to Paul's, according to the Omaha World-Herald.
But Cruz has also weighed in on the governor's race there, backing businessman Pete Ricketts, the son of Joseph Ricketts, the founder of TD Ameritrade and owner of the Chicago Cubs who created the conservative super PAC Ending Spending
Like Sasse, Ricketts is no slam dunk, either – he faces a crowded primary field that includes state Attorney General Jon Bruning and state auditor Mike Foley.
Cruz announced Thursday he would head back to the state Friday to rally for Ricketts, a gambit not dissimilar to Paul's late play in North Carolina.
Paul has since taken heat for his political judgment in North Carolina; Cruz stayed on the sidelines there.
Now, Cruz has doubled down with Paul out of the action.
If either Ricketts or Sasse pulls through on Tuesday, Cruz will receive a share of the credit and comparisons with Paul's political instincts will be inevitable.
The political class will be tempted to wonder whether Cruz is a more disciplined political tactician than Paul.
But if Sasse falls short, look for another political narrative to take shape that won't be welcome news for either Paul or Cruz – that the grass-roots insurgency they helped prop up is now losing oxygen and nearing terminal status.