Former Rep. Rob Simmons’ (R-Conn.) lead over Sen. Chris Dodd (D-Conn.) has shrunk to single digits, according to new polling results from Quinnipiac University on the 2010 Senate race.

Simmons led Dodd, 45 percent to 39 percent, with another 13 percent undecided. Also in the poll, Dodd’s disapproval rating with respondents decreased from last month’s survey results, from 58 percent to 53 percent.

Although the poll still showed Dodd as the most vulnerable Democratic Senator up for re-election next year, he rebounded from last month’s results, which showed him trailing Simmons by 16 percentage points. In a similar poll from April 2, Simmons led Dodd, 50 to 34 percent.

Simmons fared better than the only other announced Republican in the race, state Sen. Sam Caligiuri, defeating him in the GOP primary, 48 percent to 10 percent. Dodd also defeated Caligiuri in the poll, 41 percent to 39 percent in a prospective general election matchup.

Dodd has come under fire with state voters for his handling of the financial crisis as chairman of the Banking, Housing and Urban Affairs Committee, his quixotic bid for president in 2008 and an allegedly special deal he received on his home mortgage.

Dodd has even come to blows with the state’s loyal Democrats, prompting little-known Democratic businessman Merrick Alpert to run against him in the primary. Dodd defeated Alpert in the survey, 44 percent to 24 percent, with another 30 percent undecided.

The Quinnipiac University poll surveyed 1,575 registered Connecticut voters, including 614 Democrats and 385 Republicans, from May 20 to 25. The poll had a margin of error of 2.5 percentage points.