Republican Christopher J. Christie is joining the race to challenge New Jersey Gov. Jon Corzine , with supporters touting the former U.S. Attorney as their party’s best hope to win the governor’s mansion this fall.

“With strong leadership now, we can fix our broken state and make it more affordable for all New Jersey families,” Christie wrote to supporters in an e-mail, adding that a formal announcement will take place the first week of February.

Christie has earned early support from some Republicans but there is competition for the nomination. Former Bogota mayor Steve Lonegan and state Assemblyman Richard A. Merkt have already begun campaigning and additional candidates have indicated their interest.

Lonegan ran unsuccessfully for governor in the 2005 primary but has maintained a statewide profile as a conservative figure. He argues that voters are looking for conservative values such as smaller government, lower spending and low taxes during the current economic climate.

Joseph P. Cryan, chairman of the state’s Democratic party, faulted each of the declared candidates in an interview with CQ Politics. “They’ve got a right-wing small-town mayor, they’ve got an extremely conservative assemblyman and a Bush appointee,” he said. President Bush had appointed Christie to the attorney general post.

Christie’s entry into the race was expected and prompted an immediate endorsement from at least one member of the state’s congressional delegation.

“Unequivocally, Chris Christie is exactly what New Jersey needs during these challenging times. I enthusiastically endorse his candidacy for governor,” Republican Rep. Frank A. LoBiondo of the 2nd District said in a statement.

Supporters tout Christie’s record of fighting crime and prosecuting corrupt officials, citing such high-profile cases as the “Fort Dix Six,” in which five men were convicted last month of conspiring to kill soldiers at the military base, and the prosecution of former Newark Mayor Sharpe James, who was convicted of fraud last year.

“He’s a very strong leader, he’s got great management skills, he certainly understands the need for transparency in government, and he will fight for affordability for the citizens of New Jersey. He’s got a very clear record to contrast with Jon Corzine ,” state Senate Minority Leader Thomas H. Kean Jr. told CQ Politics. Kean ran for the U.S. Senate in 2006 against Democrat Robert Menendez and lost by 9 percentage points.

Republicans say this year’s race will be a referendum on Corzine’s first term and argue he has failed to solve the state’s economic problems. New Jersey, like many states, has been impacted by the national economic climate, along with facing a decline in state revenue.

“New Jersey’s taxes have become so unaffordable that more families are leaving our state than moving here,” Christie said in Thursday’s message. “Our state’s business tax climate is ranked 50th in the nation and has become so unattractive to employers that only government jobs are growing in New Jersey. Yet nothing in Trenton gets done to fix these problems.”

But Democrats say Republicans deserve the blame for the state’s economic problems, which they say are directly tied to the situation nationwide. “We’ve got a Republican mess from Bush and Bush’s policies,” Cryan said. He defended Corzine’s economic record, noting that the governor cut the state budget two years in a row.

Democratic lobbyist and political consultant Michael Murphy, who ran for governor in 1997 and whose stepfather Richard J. Hughes served as governor, argues Corzine has run a “very open, transparent administration” and has not been associated with the state’s figures of corruption. Murphy noted that Corzine remains an authority on the national economic situation as a former CEO of Goldman Sachs.