A new Mason-Dixon poll shows freshman Rep. Dina Titus (D-Nev.) in a dead heat with Republican challenger Joe Heck. Titus leads 42 percent to 40 percent, with 9 percent still undecided. 

Among unaffiliated voters, the two are tied at 39 percent. The survey polled 400 likely voters and has a margin of error of plus-or-minus 5 percentage points.

Titus is one of the National Republican Congressional Committee’s top targets in 2010, but has one early advantage — she reported more than $1.2 million cash on hand at the end of the second quarter. Heck reported just under $350,000.