Republican Liz Cheney, the daughter of former vice president Dick Cheney, will challenge Sen. Mike Enzi (R-Wyo.) in 2014, she announced Tuesday, a move that appeared to irk the senator, who announced on the same day that he is running for reelection.

"I am running because I believe it is necessary for a new generation of leaders to step up to the plate," Cheney said in a nearly six-minute Web video announcing her candidacy. In the video, Cheney sharply criticized the Obama administration, arguing that the "federal government has grown far beyond anything the pioneers of our great state ever could have imagined or would have tolerated."

Obama, she said, "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."

Cheney, who purchased a home in Jackson Hole last year, opened her announcement by underscoring her Wyoming roots, noting that her family first settled there in 1852 "in search of religious freedom." Her father represented the state in the U.S. House from 1979 to 1989.

The elder of the former vice president's two daughters, Cheney is an attorney who has worked for the State Department and the U.S. Agency for International Development. During the Bush administration, she served as principal deputy assistant secretary of state for Near Eastern Affairs.

Like her father, Cheney is hawkish when it comes to national security. In 2009, she co-founded "Keep America Safe," a nonprofit opposed to Obama's foreign policy. She has also served as a Fox News commentator. The network conformed that her contract was terminated after she announced her campaign. Networks normally sever ties with paid analysts once they become candidates for public office, in order to avoid a conflict of interest.

News of Cheney’s announcement came as Enzi was due on the Senate floor to vote on the nomination of Richard Cordray to serve as director of the Consumer Financial Protection Board. Enzi voted against the nomination.

Enzi seemed upset with the news when he spoke with reporters afterward, noting that Cheney had previously said she wouldn’t run if he decided to seek reelection.

“Obviously that wasn’t correct,” Enzi said.

Asked about his relationship with Cheney, he said, “I thought we were friends.” And Enzi admitted that Cheney’s ability to raise funds from Republicans nationwide might complicate his efforts. “Money raising’s always been a problem for me,” he said.

Regardless, Enzi insisted that he will continue with plans to run for reelection.

“My job is to be the U.S. senator that I was elected to be until at least January of 2015. The people of Wyoming expect me to do the job, I do it pretty much full time, I’m in Wyoming almost every weekend, here during the time that we’re voting out here,” he said. “I won’t be doing anything different than I’ve been doing, getting the opinions of the Wyoming people and traveling Wyoming and doing my job out here.”

Enzi fielded questions outside the Senate Chamber and stood with his Cowboy State colleague, Sen. John Barrasso (R-Wyo.), who called Enzi a friend and mentor. “He is a tremendous senator for the people of Wyoming and I plan to support him for reelection, I am supporting him for reelection,” Barrasso said. When asked, he said Cheney “is very talented and has a bright future.” Sen. Rand Paul (R-Ky.) has also signaled support for Enzi.

Enzi avoided directly commenting on Cheney during his exchange with reporters, but closed with this thought: “Nobody in Wyoming likes a long campaign – anybody from Wyoming would know that. They’ll be able to make up their mind in a lot less time than from right now until next August, which is when the primary is. You can’t even file in Wyoming until May.”

In a separate statement, Enzi, who was first elected in 1996, said he intends to run for reelection and will formally announce his bid for a fourth term at a later date.

Updated at 6:48 p.m.