WASHINGTON (AP) -- Arizona Sen. John McCain threw his support behind Wyoming Sen. Mike Enzi in his primary race against fellow Republican Liz Cheney.
The Arizona Republican told Candy Crowley on CNN's "State of the Union" that most who have served with Enzi are supporting him over the eldest daughter of former Vice President Dick Cheney.
"Mike Enzi is the epitome of a workhorse in the Senate," McCain said.
Liz Cheney launched her campaign Tuesday to unseat the three-term incumbent.
Cheney has struck a no-compromises tone, saying it's time for Republicans in Congress to stop "cutting deals" with Democrats, though she has declined to say whether she was referring to Enzi, who has expressed pride in being able to work with Democrats on some issues.
Cheney's father, who represented Wyoming in the House from 1979 to 1989, is still widely admired in his home state, yet some Republicans already are lining up behind Enzi. They include Wyoming U.S. Sen. John Barrasso and the state's lone U.S. representative, Cynthia Lummis, as well as the National Republican Senatorial Committee led by Sen. Jerry Moran, R-Kan.
Crowley asked McCain if the Enzi race shows there's a faction of the Republican Party that will challenge sitting senators from the right.
"Well, I think that may happen, and it's a free country and a free party in my view. If people want to run for the office, they can," McCain said.
A Republican primary brawl could help a Democrat seeking the office, but only if the Wyoming Democratic Party is able to transform itself quickly from the weakling it's become in recent years.
No Democrat has expressed interest in running for Enzi's seat next year, and no Democratic candidate has been competitive in a statewide race since two-term Democratic Gov. Dave Freudenthal left office in 2010.
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