Republicans will likely have a primary to determine who will challenge Sen. Chris Dodd (D) in 2010. Former Rep. Rob Simmons (R) has already announced his candidacy, and state Sen. Sam Caligiuri (R) will reportedly also announce a bid today.

According to a report in the Hartford Courant, Caligiuri asked reporters and supporters to come to his home today for an announcement “about his future plans with regards— to the Senate contest.

Dodd should have been considered a shoo-in for re-election in a Democratic state like Connecticut, but the current economic climate, a failed 2008 presidential bid and high-profile mortgage deals have caused problems for the Senate Banking, Housing and Urban Affairs chairman.

Recent polling by Quinnipiac University showed Simmons and Dodd in a virtual dead heat, 43 percent to 42 percent, respectively. But Caligiuri trailed the Senator by double digits in the same poll, 34 percent to 47 percent.

Washington Republicans encouraged Simmons early on to run for seat, but National Republican Senatorial Committee spokesman Brian Walsh confirmed that they will stay out of the primary contest.

“We have and will continue to work closely with the many individuals who want to ensure that Sen. Dodd is not returned to a sixth term,— Walsh said. “Whether because of his sweetheart real estate dealings, his moving his family to Iowa to run for President, or his failure as the Committee Chairman overseeing collapsed banking and mortgage markets — there’s no shortage of people interested in seeing him retired.—