Rep. Dean Heller (R-Nev.), right, was sworn in for a third term in the House in January. (Charles Dharapak — AP)

(This post was updated at 2:20 p.m. to reflect Krolicki’s endorsement.)

Republican Rep. Dean Heller has entered the open Senate race in Nevada, just a week after Sen. John Ensign (R) announced he would not seek reelection.

Heller, a Republican former secretary of state and a rising star in Nevada politics, announced his intentions in an e-mail to supporters.

“Your past support has meant a lot me, and for this reason I wanted you to be among the first to know that I am running for the United States Senate,” Heller says in the e-mail, first obtained by Nevada political guru Jon Ralston.

Heller enters the race as the early frontrunner to replace Ensign, who fell victim to a sex scandal following an affair with a former staffer. Ensign had been feeling out support for a potential reelection campaign over the last month, but ultimately decided against it.

Even before Ensign’s announcement, Heller was expected to enter the race. He conducted a poll earlier this year that showed him a strong favorite in a hypothetical primary matchup with Ensign.

In an interview with The Fix, Heller acknowledged that the decision was an easy one for him and that he was primed to run regardless of Ensign’s plans. But he said Ensign’s decision came more quickly than he expected.

“Obviously, we were gearing towards a primary with him,” Heller said. “It moved our timeline a couple of months forward.”

In his e-mail to supporters, Heller proudly noted that he opposed the Troubled Asset Relief Program (TARP) bailout and struck a note of fiscal conservatism. Jobs are paramount in Nevada — even more than other states — because the unemployment rate is one of the highest in the country.

Heller is not the only Republican looking at the race. Sharron Angle, who lost to Senate Majority Leader Harry Reid (D) last year, is also rumored to be a candidate. Lt. Gov. Brian Krolicki (R), who has looked at a Senate campaign, meanwhile endorsed Heller on Tuesday and says he will look at running for his House seat.

Anyone, including Angle, would have a tough time in a primary against Heller, who is popular and still carries some residual statewide name identification from his time as secretary of state. Heller represents the vast and rural 2nd district, based in Reno. The district covers all of the state outside of Las Vegas-based Clark County.

Heller told The Fix he has not spoken with Angle about her plans.

“We haven’t had those discussions, but I’m anticipating that we will,” he said.

On the Democratic side, Rep. Shelley Berkley has expressed interest in the race and appears to be getting closer to running. She has set up focus groups and is doing a poll to evaluate her chances.

“I think she’s leaning towards it,” said a source close to the congresswoman. “But she’s looking at what’s the roadmap to victory.”

Other potential Democratic candidates include Secretary of State Ross Miller(whom The Fix profiled this week), and state Attorney Catherine Cortez Masto and state Treasurer Kate Marshall have also been mentioned.