Former governor and senator George Allen will appear alongside Tito Muñoz — aka “Tito the Builder” — when the latter officially announces his candidacy for state Senate in Northern Virginia next week.

George Allen is expected to back “Tito the Builder.” (By Bill O’Leary/The Washington Post)

“George Allen is one of the great governors in Virginia history,’’ Muñoz said. “A leader of the insurgent conservative movement, he led the Republican Party back to prominence in Virginia. He created thousands of jobs, he cut taxes, and he reduced the size of state government. I am proud to have him on my side.”

Muñoz, who owns a small construction business, will run for the seat held by Democratic Sen. Linda “Toddy” Puller, which includes portions of Fairfax, Prince William and Stafford counties.

Muñoz, who formed a political action committee in April, made a name for himself when he appeared onstage with Alaska Gov. Sarah Palin during the 2008 presidential campaign. He has become a conservative Latino voice on the radio.

Allen, a former governor and senator, is the frontrunner for the Republican nomination for U.S. Senate in 2012. A Washington Post poll last month shows he remains popular even as some of his GOP opponents paint him as not conservative enough.

Last week, Jeff Frederick, ousted leader of the Republican Party of Virginia and a former Prince William County delegate, filed paperwork to run for Puller’s seat.

The Republican primary for state Senate is Aug. 23. The winner faces Puller, who has said that the district, even as redrawn by legislators in the redistricting process, remains fairly Democratic.

Updated, 4:45 p.m.: Frederick’s reaction to Allen's endorsement of his future oppnent: "I’m not running to please the political establishment, I’m running to change politics as usual in Virginia,'' he said. "The people of the Commonwealth are looking for an independent voice who is not beholden to any political class or special interests. I will always put people above politics. It is unfortunate that others in this race have decided to stand with some of the very career politicians that got us into the mess we’re in, with bigger government, massive spending, and skyrocketing debt."

 This post has been updated since it was first published.