HARTFORD, Conn. — A new Quinnipiac University Poll shows Connecticut’s US Senate race remains a dead heat.

Forty-eight percent support Republican Linda McMahon while 47 percent back Democratic US Rep. Chris Murphy, according to the telephone survey of 1,696 likely voters released Thursday.

Poll Director Douglas Schwartz said both candidates have taken hits from the recent barrage of negative TV ads.

However, Schwartz said McMahon’s supporters are more enthusiastic about their candidate. Half said they consider themselves “very enthusiastic” about the former wrestling executive, while 27 percent of Murphy’s supporters said they’re “very enthusiastic” about his candidacy.

The same poll shows Democratic President Barack Obama has a 12 percentage point lead over Republican Mitt Romney.

The survey has a margin of sampling error of plus or minus 2.4 percentage points.