Rep. Dean HellerDean HellerRed-state Dems in Supreme Court pressure cooker This week: House GOP faces make-or-break moment on ObamaCare Shutdown politics return to the Senate MORE (R-Nev.) officially announced Tuesday he's running for retiring Sen. John Ensign's (R-Nev.) seat.

Heller, who's been expected to run, made his announcement in an email to supporters.

In it, the three-term lawmaker talked up his opposition to "reckless government spending."

"As families across Nevada struggle to pay their bills and fight to keep their homes, Barack ObamaBarack ObamaSpicer: Trump is 'very confident that he will be vindicated' on surveillance claims Bush DHS secretary: 'Vladimir Putin is winning' Trump ally calls for US to roll back climate commitment MORE and his beltway allies are proposing record spending that will add to America's job-killing debt from a stratospheric $14 trillion to a staggering $20 trillion," he wrote.

"In 2008, I stood up to former President Bush, then Senator Obama, and Washington special interests and said no to the Wall Street bailout."

The announcement was widely anticipated after Ensign announced March 7 he wouldn't seek reelection in 2012.

Heller is expected to be a formidable candidate. A recent poll from Democratic-leaning Public Policy Polling (PPP) showed Heller starting ahead of every rumored Democratic candidate for the seat.

Democrats see Rep. Shelley Berkley (Nev.) as their best choice but she told The Ballot Box earlier this month she's in no hurry to make a decision.