Sen. John Cornyn (R-Tex.), the Senate's second-ranking Republican, will kick off his reelection campaign Friday at an event where he'll be joined by Texas Gov. Rick Perry (R).

Cornyn's campaign said the senator will file for reelection in Austin, where he'll also hold a rally.

The senator's kickoff comes amid uncertainty over whether he will face a primary challenger. But with a Dec. 9 filing deadline looming, no major challengers have stepped up so far.

Cornyn was elected to his second term in 2008, taking 55 percent of the vote against Democrat Rick Noriega. In the 2014 bid, he faces no well-known Democrats so far.