WASHINGTON (REUTERS) - Ms Liz Cheney, the eldest daughter of former Vice President Dick Cheney, announced that she will challenge US Senator Mike Enzi in Wyoming next year, a clash between two Republicans that some fear could damage the party.
Ms Cheney, 46, launched herself into the race with a nearly six-minute Web video in which she laid out a conservative agenda, calling the federal government too large and wasteful of taxpayer dollars, and sharply criticised Democratic President Barack Obama.
"President Obama has launched a war on our Second Amendment rights, he's launched a war on our religious freedom, he's used the IRS to launch a war on our freedom of speech and he's used the EPA to launch a war on Wyoming's ranchers, our farmers and our energy industry," she said on the video.
In announcing her first campaign for political office, Ms Cheney did not mention three-term incumbent Enzi by name but said that she was running in part "because I believe it is necessary for a new generation of leaders to step up to the plate."
"I'm running because I know, as a mother and a patriot, that we can no longer afford simply to go along to get along," said Ms Cheney, who has five children with her husband Philip Perry, former general counsel for the US Department of Homeland Security.
Mr Enzi, 69, did not comment directly on Cheney's announcement on Tuesday but said in a statement released by his campaign office that he intended to run for re-election in 2014.
"When I announce formally, I will let everyone know that date in the future. In the meantime, I will do the job I was already elected to do," said Mr Enzi, who was first elected to the Senate in 1996 and has been re-elected twice by a comfortable margin.
Ms Cheney's announcement comes as Republicans, who control the US House of Representatives, seek to regain a majority in the Senate in the 2014 elections and political analysts said a bitterly contested primary campaign could be worrisome for the party.
"The prevailing theory is she's trying to force Enzi out of the race. Because of his age, he may be uninterested in a hard re-election campaign," said Mr Larry Sabato, director of the Center for Politics at the University of Virginia.
"It's bound to a divisive race. I've found the nastiest races are those between candidates who have almost everything in common. Cheney and Enzi agree on 98 or 99 per cent of the issues, so they will have to define their differences, and often these contests become very personal and bitter," Mr Sabato said.
Mr Alan Simpson, a former Republican senator from Wyoming, told the New York Times in an interview last week that such a campaign could bring about "the destruction of the Republican Party of Wyoming," opening the door for Democrats in the state.
Ms Cheney, who describes herself in a biography on her official campaign website as a "fourth-generation Wyomingite," is an attorney who served in the US Department of State during the administration of President George W. Bush and appears on television as an analyst and political commentator for Fox News.
Her father served six terms in the US House of Representatives from Wyoming.