The Ted Cruz Effect: Can He Sway a Key Senate Race In Kansas?

— -- It’s been one year since the 16-day government shutdown. At the time, it was a move that appeared to work in favor of Democrats eager to paint figures like Sen. Ted Cruz and other Republicans as obstructionists favoring brinksmanship over compromise.

But times have changed, and now Cruz, R-Texas, is set to spend part of the anniversary of the shutdown in Kansas, helping out endangered Sen. Pat Roberts, the three-term incumbent who faces his toughest challenge yet against an Independent candidate preaching centrism.

Roberts’ campaign announced Monday that Cruz will join Roberts in the kick-off Thursday of a four-day bus tour along with retiring Oklahoma Sen. Tom Coburn.

“I am proud to call Pat Roberts a friend and to endorse him in this important race for U.S. Senate,” Cruz said in a statement released by the campaign. “One year ago, Pat stood by my side in the fight to defund Obamacare, and he will continue to fight against intrusive liberal policies in the U.S. Senate.”

Cruz is referring to Roberts standing with him during his 21-hour filibuster in protest of the Affordable Care Act in late September 2013. The move brought scrutiny from moderates inside the Republican Party and helped make Cruz one of the GOP’s most polarizing figures.

Several sources in the state say inviting Cruz could alienate more moderates from Roberts, many of which have already found favor with the policies put forth by Roberts’ opponent Greg Orman.

Roberts’ campaign announcement came along with an official endorsement from Cruz, and Orman’s campaign quickly responded.

“Inviting the architect of last year's government shutdown to Kansas is yet another example of how Senator Roberts is an enthusiastic participant in a broken system,” said Orman campaign manager Jim Jonas in a statement. “Washington is a mess of dysfunction, extreme partisanship and gridlock, and Senator Roberts is part of the problem.”

In an interview with ABC News, Wichita State professor of politics H. Edward Flentje said by adding Cruz, Roberts is looking to revive support from the state’s unenthusiastic Tea Party members.

“There is talk that a lot of the Tea Party members in the state are planning to sit out the race entirely,” Flentje said. “Roberts lost a lot of friends during his primary with [Tea Party opponent Milton] Wolf, and I think his campaign staff is doing everything it can to bring folks back in.”

Roberts' campaign manager Corry Bliss said the support Roberts has received from Republicans including Mitt Romney, Rep. Paul Ryan and Sen. Bob Dole shows Republicans are refusing to accept Orman’s claims of being an Independent.

“Republicans are uniting around Sen. Roberts for one reason, and that’s that every Republican agrees that a vote for Greg Orman is a vote for the Barack Obama, Harry Reid liberal agenda,” Bliss told ABC News. “Last week Barack Obama said that this election is about his policies, and these Republicans are coming to the state because there is only one candidate that is proven to be against those policies.”

Flentje said Cruz could help mend fences with many of the Tea Party members in the state, but he said he also could risk doing more harm than good.

“He’s already offended a lot of moderate Republicans with his shift to the right,” Flentje said. “This along with [Roberts] inviting Sarah Palin to campaign with him kind of seems to reaffirm most of that criticism.”